Midterm Flashcards
1
Q
What do hormones increase the probability of?
A
A behavior occurring
2
Q
__% of brain is glia
A
90%
3
Q
How can you strengthen a synapse?
A
By increasing dendritic spines or receptor density
4
Q
Nigrostriatal pathway
A
active in maintaining normal motor behavior
loss of DA is related to muscle rigidity (Parkinsons)
5
Q
Mesolimbic pathway
A
DA release causes feeling of reward and pleasure
NT system most affected by addictive drugs
6
Q
Hormones
A
Chemical messengers released from endocrine glands that travel through the blood stream to influence the nervous system and regulate the physiology and behavior of an organism
7
Q
Where do hormones come from?
A
hormones are produced by glands and secreted into blood
8
Q
Where do hormones go?
A
They travel in the blood to target tissues containing specific receptors for the hormones
9
Q
What do hormones do?
A
By interacting with their receptors, hormones initiate biochemical events that can activate gene expression (via intracellular receptors) or induce fast, non-genomic effects (via membrane receptors)
10
Q
Main function regulated by secretion of hypothalamus?
A
Control of hormone secretions
11
Q
Main function regulated by secretion of pineal gland?
A
Reproductive maturation; body rhytms
12
Q
Main function regulated by anterior pituitary secretion?
A
hormone secretion by thyroid, adrenal cortex, and gonads; growth
13
Q
Main function regulated by posterior pituitary secretion?
A
water balance; salt balance
14
Q
Main function regulated by thyroid secretion?
A
growth and development; metabolic rate
15
Q
Main function regulated by adrenal cortex secretion?
A
salt and carbohydrate metabolism; inflammatory reactions
16
Q
Main function regulated by adrenal medulla secretion?
A
emotional arousal
17
Q
Main function regulated by pancreas (islets of Langerhans) secretion?
A
sugar metabolism
18
Q
Main function regulated by gut secretion?
A
digestion and appetite control
19
Q
Main function regulated by gonads (testes/ovaries) secretion?
A
body development; maintenance of reproductive organs in adults
20
Q
Neuronal Transmission
A
electrochemical communication. fast, highly specific. NTs are released over a short range (synapse)
21
Q
Hormonal Communication
A
long-range, slow, very widespread. coordinates response across whole-organism
22
Q
2 advantages of global communication for hormones?
A
- Developmental: coordinated transformation of all cells in an organism
- Coordination of a body’s response to an environmental trigger
23
Q
Negative Feedback System
A
How hormone production is regulated.
The production of a hormone by the target tissue (e.g cortisol from adrenals) feeds back to the source of the hormone to stop production
24
Q
Hormone action on the brain
A
A hormone secreted from an endocrine gland travels through the blood stream to target tissues (including the brain)
25
Steroid hormones & blood brain barrier
Steroids are lipophillic (fat loving) and can pass through the phospholipid bilayer
26
De Novo
Brain has all machinery to make hormones
27
Areas in the brain with dense receptors suggests what?
Higher sensitivity to that hormone
28
For every hormone there are ___ receptors in the brain
unique
29
3 things a hormone does once it binds to a receptor in a brain cell?
1. might change membrane potential, making it easier or harder to start an action potential
2. could impact gene transcription, mechanism for increasing/decreasing receptor expression
3. change protein expression (e.g stimulate NT synthesis)
30
4 behaviors that hormones influence?
stress
memory
aggression
depression
31
6 brain regions in the limbic system?
```
thalamus
nucleus accumbens
hypothalamus
amygdala
hippocampus
VTA
```
32
Odine's Curse
lesion to midbrain region and you lose capacity to do automatic breathing. you die of sleep deprivation
33
What role does amygdala have in limbic system?
fear, anxiety, aggression
34
What role does hippocampus have in limbic system?
turns off stress response
35
What is the last part of the brain that matures?
frontal cortex
36
What is the best predictor for how large the frontal cortex is in a species? What does this suggest?
The average size of their social group
Suggests that this part of the brain evolved for gossip and social intelligence and social behavior
37
3 classes of evidence to establish hormones-behavior relationship
1. the behavior disappears when the hormone is removed or blocked
2. replacing the hormone reinstates the behavior
3. hormone concentrations and the behavior covary (behavior occurs when hormone concentration is high; never or rarely when hormone concentrations are low)
38
4 levels of analysis as to what causes zebra finches to sing?
1. immediate causation
2. development
3. evolution
4. adaptive function
39
Ablation & Replacement Steps (Behavioral Endocrinology Techniques)
1. Gland that's suspected to be the source of a hormone affecting a hormone is surgically removed
2. The effects of removal are observed
3. The hormone is replaced by re-implanting the removed gland, or injecting a purified hormone
4. Determine whether the consequence of ablation is reversed by replacement therapy
(e. g Berthold's experiment)
40
RIA (radioactive immunoassay)
A technique for determining antibody levels by introducing an antigen labeled with a radioisotope and measuring the subsequent radioactivity of the antibody component
41
EIA (enzyme immunoassay)/ELISA (enyzme-linked immunoassay)
Both techniques are based on the principle of immunoassay with an enzyme rather than radioactively as the reporter label
Home pregnancy tests use a form of EIA
42
Immunocytochemistry
Identifying neurons that produce a particular hormone or NT
Where in the body is the hormone or hormone receptor?
1st antibody - against NT
2nd antibody - labeled
Technique that uses antibodies to determine the location of a hormone or hormone receptor in body
The range of microscopic techniques used in the study of the immune system
43
What kind of samples is immunocytochemistry performed?
On samples consisting of cells grown in a monolayer or cells in suspension which are deposited on a slide, relies on same enzyme reactions as IHC
44
Immunohistochemistry
Where in the body is the hormone or hormone receptor?
Test to detect antigens (e.g proteins) in cells of tissues by exploiting the principle of antibodies binding to specific antigens
45
What kind of samples is immunohistochemistry performed?
Performed on samples derived from tissues that have been histologically processed into thin sections and the staining process exploits enzymes which catalyze the deposition of a colored staining product at antigenic sites within sample
46
1) Estrogen receptors could be localized where in the brain?
| 2) Estrogen receptor colocalized with cells staining for what NT? As well as what 2 receptors containing neurons?
1) Both neurons and astrocytes
| 2) Dopamine, D1A, D2
47
Autoradiography
A technique used to detect a radio labeled substance, such as a hormone, in a cell or organism, by placing a thin slice of the material in contact with a photographic emulsion
48
Autoradiograph
Image on an x-ray film or nuclear emulsion by the pattern of decay emissions (e.g beta particles or gamma rays) from a distribution of a radioactive substance
49
In Situ Hybridization
A technique in which nucleic acid probes are used to locate specific nucleic acids (DNA in chromosomes and RNA in cells)
Not at the protein but at the level of gene expression to identify tissues that show specific protein (hormone, receptor, etc)
Stain for something specific (e.g oxytocin)
50
Pharmacological Techniques
The use of chemical agents that may alter the action or function of a hormone
2 major groups referred to as agonists and antagonists
51
Agonists
Hormone mimics
52
Antagonists
Hormone blockers
53
2 ways agonists and antagonists can be administered to an animal?
Cannulation: Chronic indwelling
Single injection: using a syringe and needle
54
In general, what are tract tracing methods used to map?
A neural circuit
Where does a particular cell project
You see what's stained after it's injected
55
Anterograde tract tracing
Inject tracer in cell body, and explore cell's axonal projections
Let it diffuse along axonal projection to see where it ends up
How a cell body might be producing a certain hormone, where it's branching off to, etc
56
Retrograde tract tracing
At fiber terminals, and examine location of cell body
Injection is going backward
57
Knockout/in mice
Produce mice in which a specific gene has been deactivated (knocked out)
Use DNA, or a mutant copy of gene you're interested in
Take cells that have one mutant copy and introduce it into embryo or astrocyte
Through selective breeding paradigms, you can get mice that have wild-type or double knockout
You can make hypothesis about which receptors are used in certain roles
58
(Knockout/in mice) forms of estrogen receptor knockout mice
Wild-type: normal, what you would expect to see
Alpha: less branching; selective knocking out produces change in mammary glands in alpha, but not beta
Beta: looks similar, fully developed duct network
59
Optogenetics
Newer techniques, last 10-15 years.
Both probing and manipulating function of nervous system.
You engineer mice that have a special ion gate that are light activated.
Put ion channels in different neurons, ex) dopamine neurons (whatever you want to manipulate, you can activate or inhibit specific neurons, you can see how activating a specific area *it's called cell specific* you can see what effects that has on specific circuit)
Can drive specific cell types, exquisite experimental control over neurons
You can look at multiple layers (e.g lamina throughout cortex)
Beautiful, large scale volume layerts
60
What is leptin released from (a decade ago)?
Adiopose (fat) cells
61
Leptin mutation in mice that causes obesity
Someone discovered there was a mutation in mice that causes extreme obesity, if it develops two copies of this defective gene, they're homozygous - they become hyperphagic - they over eat & reproductively sterile
62
Ob gene
codes for leptin
| travels to CNS to regulate
63
Intracrine Mediation
Intracrine (hormone that acts inside a cell) substances that regulate intracellular events
64
Autocrine Mediation
Autocrine (cell secretes a hormone that binds to autocrine receptor on same cell) substances feedback to regulate the same cell that secreted them
65
Endocrine Mediation
Endocrine cells secret chemicals into the bloodstrem, where they may travel to distant target cells
66
Paracrine Mediation
Paracine cells that secrete chemicals that affect adjacent cells
67
Ectocrine Mediation
Ectocrine substances, such as pheromones, are released into the environment by individuals to communicate with others
68
Chemical Messenger
Any substance that's produced by a cell that affects the function of another cell
69
Cytokine
A chemical messenger that evokes proliferation of other cells, especially in the immune system
70
Hormone
A chemical messenger that's released into the blood stream or tissue fluid system that affects the function of target cells some distance from the source
71
Neurohormone
A hormone produced by a neuron
72
Neuromodulator
A hormone that changes (modulates) the response of a neuron to some other factors
73
Neuropeptide
A peptide hormone produced by a neuron
74
Neurosteroid
A steroid hormone produced by a neuron
75
Neurotransmitter
A chemical messenger that acts across the neural synapse
76
How is the pituitary gland connected to hypothalamus?
by median eminence
77
One important feature of the major endocrine glands?
Highly vascularized, they harness the bloodstream to travel
Thyroid is the most highly vascularized in entire body
78
If you want to control hormones without agonists or antagonists what do you do?
speed up or slow down vascular flow
79
The human pituitary is the size of what?
a blueberry, yet it secretes many hormones
80
Anterior and posterior pituitary have different one?
embryonic origins and function
81
What is called the "conductor of endocrine orchestra"?
Posterior pituitary, weighs 1 gram (like a paper clip) yet it controls all major endocrine systems and completely indispensable for life
82
Together, the hypothalamus and pituitary serve to regulate what?
Many peripheral endocrine glands
83
Where does the hypothalamic nuclei integrate info from? What does it coordinate?
other parts of the brain
coordinates physiological, bodily processes
84
Neurosecretory cells
at the base of hypothalamus
very similar to conventional neurons but they release neurohormones, they're released into blood vessels into pituitary gland
85
Releasing hormones
What hypothalamus releases
86
Hypothalamus is located at _____ and communicates with the ____ via ___ and ___
base of brain
pituitary
blood and neurons (axons)
87
When projecting to the anterior pituitary, where do hypothalamic axons project? What does it carry?
project to portal system which carries releasing factors to the anterior pituitary
88
How does anterior pituitary cells responds to the releasing factors (RF)?
They release their own tropic hormones into general circulation
89
(Hypo-Anterior PS) Peripheral glands release hormones that have ___ effect
Metabolic
90
(Hypo-Anterior PS) what kind of feedback do peripheral hormones tend to provide to both the hypothalamus and anterior pituitary?
Negative feedback
91
When projecting to the posterior pituitary, where do hypothalamic neurons project axons to?
The posterior pituitary (post. pituitary made up of axon terminals)
92
Posterior pituitary
Made up of axon terminals, releases hormones from hypothalamus into blood
93
What hormones does the posterior pituitary release?
Vasopression (AVP or ADH) & oxytocin
Released in response to action potential, causes exocytosis of cell into bloodstrem
94
Magnocellular neurosecretory cells
in hypothalamus - sends axons all the way down to synapse on blood vessels in posterior pituitary
95
HPG Axis regulates what?
sexual development & behavior
96
HPA Axis regulates what?
the stress response
97
HP Axis for Thyroid helps regulate what?
Energy metabolism
98
Vasopressin
Regulates water & sodium balance
Blood pressure, etc
Also activated in a stress response
99
Oxytocin
Hormone related to social behavior
Bonding, trust & relationships
100
Neuroendocrine Pulsatility
Refers to the coordinated, intermittent release of hormones by a population of neurosecretory cells
With chronic stimulation, the hypothalamus is going to release GnRH but the pituitary stops being responsive after a while
101
What is the largest class of hormones?
Protein and peptide hormones
102
How come protein and peptide hormones travel feely through blood?
They're water soluble
103
Where are protein and peptide hormones stored? They're released via what?
Stored - endocrine cells
Released via exocytosis
104
How do protein and peptide hormones show species specificity?
They're structurally heterogenous
105
What kind of receptors are for protein and peptide hormones?
Transmembrane receptors (G-protein coupled receptors; Enzyme-linked receptors)
106
Hypothalamic hormones that are protein and peptide hormones?
GnRH
CRH
TRH
GHRH
107
Pituitary hormones that are protein and peptide hormones?
LH
FSH
ACTCH
Oxytocin
108
All steroid hormones are synthesized from what?
Cholesterol (amino acid sequence is highly conserved among vertebrates)
109
How come steroid hormones diffuse easily through cell membrane?
Small, fat soluble
110
How do steroid hormones move through blood?
Use chaperones bc they're not water soluble
111
What kind of receptors are for steroid hormones?
Intracellular and membrane receptors
112
What steroid hormones are secreted from adrenal glands?
Cortisol
| DHEA
113
What steroid hormones are secreted from gonads?
Testosterone
Estrogen
Progesterone
114
What steroid hormones are secreted from brain?
Neurosteroids
115
3 things blood concentrations of steroid hormones are governed by?
1. rate of steroid biosynthesis
2. rate of steroid inactivation (catabolism)
3. "tenacity" (affinity) of binding between hormone and plasma carrier protein
116
Steroid hormones are never ___
stored
117
Steroids are released as they're what?
Synthesized
118
What do steroid hormones bind to in the circulatory system?
Water-soluble carrier proteins
119
Levels of steroid are regulated by what?
Control (e.g phosphorylation) of enzymes that convert cholesterol to active hormones
120
4 Structural Classifications of Hormones
Protein/Peptide Hormones
Steroid Hormones
Monoamines
Lipid-Based Hormones
121
Prohormone
a substance that can act as a hormone itself or can be converted into another hormone that has different endocrine properties
122
Spermatogenesis
Production or development of mature spermatozoa
123
4 things androgens play a role in?
Male secondary sex characteristics (e.g body hair in humans, comb size in roosters)
Courtship/copulatory behavior
Aggression
Muscle Mass
124
What are androgens aromatized (convert into an aromatic structure) into?
Estrogens
125
Levels of a given steroid are regulated by what?
The presence of absence of enzymes that convert cholesterol to the active hormone
126
In the ovaries, enzymes convert testosterone to what?
Estrogen
127
5 estrogen functions
formulation of corpora lutea
secondary sex characteristics
bone mass
metabolism
sexual behavior
128
Corpora Lutea
Yellowish mass of progesterone-secreting endocrine tissue that forms immediately after ovulation from the ruptured graafian follicle in the mammalian ovary
129
Why are androgens and estrogens neither male nor female?
All male vertebrates produce some estrogen and progestins; all female vertebrates produce androgens
130
What is the difference in androgen and estrogen between the sexes?
The relative concentration of these circulating hormones
131
What is the difference in androgens and estrogens between the sexes driven by?
The amount of converting enzymes present in the gonads or elsewhere
132
Where are neurosteroids produced?
in the CNS in glial cells
133
Neurosteroids synthesis
Synthesized 'de novo' (anew) from cholesterol
Synthesis is independent of steroidogenic activity in other endocrine glands
134
3 examples of neurosteroids
progesterone
pregnenolone
DHEA
135
Function of Neurosteroids
Modulate neurotransmitter receptors or undiscovered hormone receptors (e.g progesterone receptor evident in CNS)
136
Classic Steroid Hormone Receptors
Are intracellular
137
Hormone-receptor complex
Transcription factor
Steroids
Binds to HRE on DNA to initiate gene transcription
138
3 major domains of steroid hormone receptors?
1. steroid hormone binding site (C-terminal domain)
2. DNA binding site (central domain)
3. Site for other DNA binding proteins to attach (N-terminal domain)
139
Steroid-receptor complex binds to what to evoke what?
Binds to specific HRE on DNA to evoke activation or suppression of gene transcription
140
What guides the steroid-receptor complex to the right HRE?
Co-activators
| Mechanism unknown
141
Non-genomic action of steroids (What has a number of findings indicated over the last 10 years?)
That steroids produce rapid (<10 min) behavioral effects not accounted for by changes in gene expression
142
Estradiol example of non-genomic actions of steroids
Estradiol's ability to potentiate dopamine release
Bases of explaining non-genomic effects of steroids
143
Non-genomic
Modulating ion channels, interacting with NT receptors, membrane receptors for steroids
144
Genomic Action of Steroids
Slow, steroid hormone binds to intracellular receptor in cell -> genome interaction; increased protein synthesis -> latency of hours
e.g drive transcription of new proteins
145
Non-genomic Actions of Steroids
Fast, steroid hormone binds to receptor on membrane of cell/intracellular receptors -> increased second messenger and kinase activity -> latency of seconds
e.g alter membrane permeability
146
2 ways hormones can regulate their own production?
Positive feedback loops
| Negative feedback loops
147
2 ways hormones can up-regulate or down-regulate receptors
Homospecific priming (regulate own receptor)
Heterospecific priming (regulate other hormone receptor)
148
Signal Transduction Pathways
A set of chemical reactions in a cell that occurs when a molecule, such as a hormone, attaches to a receptor on the cell membrane
Pathway - actually a cascade of biochemical reactions inside the cell that eventually reach the target molecule or reaction
149
All protein hormones share same what?
Basic structure
150
2 functional classes of protein and peptide hormone receptors?
1. intrinsic enzyme activity (tyrosine kinase)
| 2. second messengers (GPCR's)
151
Enzyme Amplification
A series of chemical reactions in which a single hormone has the cascade effect which triggers the production or activation of up to a billion enzymes
152
3 steps of tyrosine kinase receptor activation
1. When receptor is unoccupied, the tyrosine kinase domain is inactive
2. After binding of hormone, the tyrosine kinase domain changes shape to allow for interactions with protein kinases
3. ATP phosphorylates (introduce a phosphate group) and activates the protein kinase, which affects cell function
153
GPCRs are an example of a protein receptor that requires what?
A second messenger to carry out a hormonal signal
154
Sexual Differentiation
The process by which individuals develop the characteristics associated with being male or female
155
Sex Determination
the point at which an individual begins to develop as either a male or female
156
5 levels of sex determination
Chromosomal sex -> gonadal sex -> hormonal sex -> morphological sex -> behavioral sex (chromosomal points to behavioral)
157
Chromosomal sex of females
Homogametic mammals (XX)
158
Chromosomal sex of males
Heterogametic mammals
| XY
159
Gametic sex of females
Ovaries produce eggs (limited #, large, immobile)
160
Gametic sex of males
Testes produce sperm (large #, small, mobile)
161
5 things males/females differ in morphological sex?
1. size
2. external genitalia
3. coloration
4. size of horns/antlers
5. ornamentation
162
Gender Identity
Self-ascribed gender in humans
163
Gender roles
Culturally based summary of sex-specific behaviors in humans
164
Asexual Reproduction (Parthenogenesis)
Asexual reproduction is very efficient
Parthenogenesis: reproduction from an ovum without fertilization, especially as a normal process in some invertebrates and lower plants
165
Why is asexual reproduction rare in vertebrates?
Evolutionary answer - sexual reproduction allows for a wide range of genetic diversity; makes a population more likely to be able to adapt to changing conditions
166
Sexual Reproduction
The recombination of genetic material allows for genetic variability.. variability on which natural selection can act
167
Sexual reproduction leads to a species being more what?
Resistant to a major environmental change
168
Dimorphic
Having 2 different forms; usually refers to differences between 2 sexes
169
Polygamous vs. monogamous species & sexual dimorphism
Polygamous species (multiple mating partners) show more sexual dimorphism than monogamous species (single mating partner)
170
Males are ___,___, more ___, higher ___
larger
stronger
more aggressive
higher mortality
171
Typically, ___ compete, ___ choose
males compete
| females choose
172
Why do 2 sexes differ in appearance/behavior?
Sexual selection - act to favor certain traits among competing sex
173
Bowerbirds & Sexual Selection
1. Are bowerbirds polygamous or monogamous?
2. Females select males based on what 2 characteristics?
3. What do characteristics signal? (Dull feathers = ? Simple bower = ?)
4. Males competing made them evolve to be ___, more ___, more ___
1. polygamous
2. males morphological (coloration) and behavioral (bower) characteristics
3. Characteristics signal gene quality (dull feathers = higher internal parasitic load; simple bower = higher environmental parasitic load)
4. evolved to be bigger, more colorful, more aggressive
174
Males of polygamous species tend to explore ___ territory
Larger
175
Do males of monogamous specie have poorer direction finding skills or spatial aptitude than polygamous males? What's this associated with?
Yes; associated with a dimorphism in hippocampus
Polygamous: hippocampus males > females
Monogamous: hippocampus males = females
176
Sexual Dimorphic Behaviors
Behaviors that are different in males & females
Include courting, mating, parental behavior, most forms of aggressive behavior
177
What can play a role in the development and control of sexually dimorphic behaviors?
Hormones
178
Gonadal Steroid Hormones (How do hormones guide behavioral sex differences?)
Organizational and activational effects on brain
179
(Gonadal Steroid Hormones) Organizational (programming) effects on brain
1. Early in development and puberty; irreversible
2. Differential exposure to hormones act early in development to organize neural circuitry underlying sexually dimorphic behaviors
180
(Gonadal Steroid Hormones) Activational effects on brain
1. in adulthood
2. temporary; may wane after the hormone is metabolized
3. differential exposure to sex steroid hormones later in life "activate" the neural circuit previously organized
181
Dynamic Model for Sexual Differentiation
Sex differences arise due to the actions of hormones during early development, during puberty, and during adult life. Experience plays an important role, as well, and interacts in an epigenetic fashion with the ongoing influences of hormones at various stages of development
182
When does the first step of mammalian sexual differentiation occur?
At fertilization
183
Germinal Ride
Gonadal development of the human embryo
```
Bipotential primordial (exist at beginning of time) gonad
Can become ovary or testis
```
184
SRY gene
Sex-determining Region of Y chromosome
185
What happens if SRY gene is present?
Testis determination factor protein -> testis formation
186
What happens if SRY gene is absent?
Ovary formation
187
Wnt4
Gene that may be required for ovarian development
188
Hormonal secretions from developing gonads guide what?
Development
189
What do mice that are chromosomally XY but do not have the SRY gene develop?
Ovaries
190
XX transgenic mice that have SRY inserted develop what?
Testes
191
Accessory Sex Organs
The internal organs of the male and female reproductive tract that connect the gonads to the external environment
Mullerian duct system
Wolffian duct system
192
When is the mullerian duct system and wolffian duct system both present in both sexes?
During embryonic development
193
When does one system develop and the other regress?
During 1st trimester
194
Mullerian duct system
Ovaries or absence of any gonads
No MIH or androgen
Female
195
Wolffian duct system
Testosterone/androgens and MIH required
| Male
196
Defeminization
Mullerian duct regression (MIH dependent)
197
Demasculinization
Wolffian duct regression
198
5alpha-reductase
Standard development of the external genitalia
Converts T to DHT
Present in embryonic genitals in M and F
199
In the standard development of the external genitalia, what happens if unusually high (androgens) are present in females?
Some T will be converted to DHT, leading to male external genitalia
200
In the standard development of the external genitalia, what happens if males lack 5alpha-reductase?
Males that lack the enzyme have female-typical external genitalia
201
In the standard development of external genitalia, what happens if females lack 5alpha-reductase?
Females that lack the enzyme have external genitalia
202
Congenital Adrenal Hyperplasia
A genetic deficiency that results in the overproduction of androgens by the adrenal glands
Syndrome has no reported effects on genital differentiation in males but causes various degrees of masculinization of the external genitalia in females, which may lead to erroneous (wrong) assignment of sex at birth
Partial masculinization
203
Complete Androgen Insensitivity Syndrome (CAIS)
Anomalous (deviating from what's normal) sexual differentiation in XY individuals
No functional androgen receptors
Genetic mutation on X chromosome (gene for AR) causes insensitivity to andorgens
Genetic XX females with mutation suffer no ill effects
204
Genetic XY males with Complete Androgen Insensitivity Syndrome (CAIS)
1. Have SRY gene -> gonads are testes, androgen production
2. Testes produce MIH -> regression of Mullerian duct
3. No AR, so Wolffian duct is underdeveloped
4. Individuals have female external genitalia, sexed/reared as girls
5. No uterus, fallopian tubes, sterile, typical female body shape
205
William C Young studied what?
The effects of hormones on sexually dimorphic behaviors
206
Sexually dimorphic mating postures
Lordosis in females
| Mounting in males
207
(Mating behavior is under the control of gonadal steroid hormones)
1. Castrate males - ?
2. T replacement - ?
3. Does T cause mounting?
4. T replacement in females - ?
5. Male vs. female behavior
1. No mounting behavior
2. Resumes mounting
3. No
4. No Mounting
5. Female behavior "de-masculinized", male behavior "de-feminized"
208
(Effects of hormones on sexually dimorphic behaviors)
| How are these differences in hormonal response mediated hypothesis?
Hormonal events early in development must be responsible for the induction of feminine and masculine behavior
209
William C Young's Experiment on giving pregnant guinea pigs T throughout gestation
1. Large T dose: females had male external genitalia "hermaphrodites"
2. Small T dose: female genitalia "unmodified"
3. Animals matured, gonadectomized; administered T; observed mounting behavior
4. Females primed with T early in development and again in adulthood displayed the male typical behavior (mounting, not lordosis)
210
Prenatal action of hormones causes what?
Differentiation/organization of neural substrates for behavior
211
Adult hormones activate what?
Activation of previously organized substrates seen in prenatal action
212
Even females whose external genitalia are not physically masculinized demonstrate what?
Behavioral masculinization and defeminization
213
Puberty
Reproductive maturation guided by a sequence of timed neuroendocrine events
214
Adolescence
Transitional period between childhood and adulthood. Psychological, cognitive, social, cultural aspects
215
2 consequences of puberty that are energetically expensive?
1. defense of territory or partner
| 2. pregnancy and caregiving
216
Puberty begins as an integration of what 3 cues?
metabolic
social
environmental
217
Adrenarche
Adrenal androgen secretion (DHEAS)
218
Gonadarche
Gonadal production of steroid hormones
219
Thelarche
Breast development in girls
220
Pubarche
Axillary and pubic hair growth
221
Menarche
Onset of menstruation
222
What's the first overt sign of puberty in girls & boys?
Girls - thelarche
| Boys - testicular enlargement
223
Typical age of puberty onset for girls
8-12 years
224
Typical age of puberty onset in boys?
9-14
225
The puberty transition lasts how long?
3-4 years
226
Early menarche in girls is a risk factor for what 5 things?
```
breast cancer
CVD
depression
diabetes
all-cause mortality
```
227
Early puberty in boys can result in what 2 things?
testicular cancer
| psychosocial distress
228
When was there a decrease in average age of menarche/thelarche?
19th to 20th century
229
Racial/ethnic differences in puberty; what % of non-hispanic caucasians, african americans, hispanics, and asians had start developing breasts by age 7?
10% non-hispanic caucasians
23% african american
15% hispanic
2% asian
230
What environmental factors could cause early onset of puberty?
BPA
231
What psychosocial factors could cause early onset of puberty?
Family stress: maternal depression/absent parent
232
Precocious Puberty
<8 years in girls
| <9 years in boys
233
Central precocious puberty
Early maturation of HPG axis
GnRH dependent
Tumors, chronic sex steroid exposure
60% idiopathic (spontaneously)
234
Peripheral precocious puberty
Early hormone production from peripheral glands
235
Delayed puberty
>13 years in girls
| >14 years in boys
236
Hypogonadism
>18 years puberty
237
Hypogonadotropic Hypogonadism
In CNS
Deficiency in GnRH secretion
Genetic defect in 40% of known cases
Organic causes: tumor, drug use
238
Hypergonadotropic hypogonadism
Outside CNS
| Defect in the gonads
239
What is the primary mechanism by which the body alters its reproductive status during development?
Changing the pulse frequency of GnRH
240
Puberty onset requires finely tuned ____ control of ____ release from neurons in the ___
temporal
GnRH
hypothalamus
241
Strong ___ component to the timing of puberty
genetic
242
What kind of neurons are central to gonadal maturation?
GnRH
243
What kind of hormone is kisspeptin?
Newly discovered small peptide hormone
244
What gene is kisspeptin encoded by? Binds with high affinity to what receptor?
```
Kiss1 gene
KISS1R receptor (GPR54)
```
245
Human and mice with mutated KISS1R have what impaired function?
impaired reproductive function
246
Where are neurons that express kisspeptin localized to?
hypothalamic nuclei that control GnRH neuron activity
247
What neurons releases kisspeptin and what does this release stimulate?
KNDy neurons stimulates GnRH
248
What is kisspeptin essential for?
GnRH secretion
LH
ultimately puberty
249
A single injection of kisspeptin in animals leads to a huge increase in what?
secretion of gonadatropics
250
Repeated injections of kisspeptin in immature rats advances what?
age of puberty
251
Blocking kisspeptin in rats will stop what?
estrous cycle
252
Does inhibiting kisspeptin even after puberty block reproductive function?
yes
253
Adiminstering kisspeptin to food-restricted animals stimulaes what?
gonadatropins
254
In seasonal-breeding animals, what is kisspeptin controlled by?
Duration of daylight
255
During short winter days; ___ kisspeptin, ___ sexual acitivity
reduced
| no
256
Long summer days; ___ kisspeptin, ___ breeeding
increased
| stimulates
257
What does artificial injections of kisspeptin in winter stimulate?
ovulation
258
Clinical Implications of Kisspeptin: Treatment for precocious puberty
taking pills with kisspeptin derivative
259
Clinical Implications of Kisspeptin: Treatment for delayed puberty
Admin kisspeptin to kickstart the process
260
Clinical Implications of Kisspeptin: Infertility treatment
Kisspeptin can start reproductive function in women who have stopped ovulating due to a steroid hormone imbalance
261
Initiation of puberty (Kisspeptin, Kiss1 gene, PcG repressor proteins)
1. kisspeptin stimulates GnRH neurons
2. Expression is Kiss1gene is suppressed by a complex of proteins: PcG repressor proteins
3. Epigenetic changes to Kiss1 promotor region releases the proteins and allows gene transcription to proceed
262
MKRN3
Inhibits of HPG axis in control of puberty onset
263
Role of environment in age of pubertal onset: What 2 things are thought to be causally linked? What is the inverse correlation?
Historical decrease in the age of sexual maturation (especially for girls) and increase in body weight
Inverse correlation between body mass index and pubertal onset in girls1
264
Precocious puberty is 10x more likely in ____
girls
265
Delayed puberty is 5x more common in ___
boys
266
2 peripheral metabolic hormones that have metabolic control of GnRH secretion?
Leptin
| Ghrelin
267
Where is leptin stored?
Adipocytes
268
What is leptin highly correlated with?
Fatt mass
269
Leptin (___ factor, permissive signal to ___, signals size of ___)
satiety
HPG axis
energy reserves
270
Where is ghrelin?
Stoomach
271
Ghrelin signals ___, inhibits ___
signals energy insufficiency
inhibits GnRH pulsatility
272
When does grey matter peak in boys & girls? What's it followed by?
11 - girls
12 - boys
followed by cortical pruning/thinning
273
What mechanisms are responsible for maternal and paternal behavior?
Neuroendocrine mechanisms
274
What is parental investment and style based on?
The developmental state of offspring at birth and their growth trajectory
275
Maternal care across species zoo incidents example (Binti Jua vs. Harambe)
Binti Jua - 8 year old female gorilla, new mom to 17 month old baby, lactating, caregiving/agression
Harambe - 17 year old male gorilla, nonparental dominant male
276
Parental Investment Theory: Parental style/investment varies widely within and between ___
species
277
Parental Investment Theory reflects an optimal ____ strategy for maximizing ___
evolutionary
| fitness
278
Parental Investment Theory: Optimal strategy
Provide care, but no more than absolutely necessary
279
Parental Investment Theory: Parental investment
The extent to which parents compromise their ability to produce more offspring in order to care for the young they have
280
Parental Investment Theory: The sex making the larger investment in feeding/protecting is ___ in selecting mate
choosier
281
Parental Investment Theory: The sex that contributes fewer resources to offspring success ___ among themselves to be chosen
competes
282
Parental Investment Theory: Tradeoff between what 2 things?
investing in reproduction and parental care
283
Parental Investment Theory: if a single female can sufficiently care for her young, what will male do?
make other "reproductive investment" to increase his fitness
284
Parental Investment Theory: What could happen to the fitness of both parents if they both abandon young?
both parents could suffer
285
Parental Investment Theory: in most cases, males become involved in parental care only if what?
the offspring needs high levels of care from 2 parents
286
Parental Behavior
Behaviors performed in relation to one's offspring that contribute directly to the survival of fertilized eggs or offspring that have left the body of the female
287
Altricial
Born or hatched at an early stage of development.
Altricial offspring are generally helpless and require substantial parental care to survive.
Large number of immature young
Mothers may or may not display parental care
288
Precocial
Born or hatched at an advanced stage of development. Precocial young require little or not parental intervention for survival
Few number of well-developed offspring
Can survive with little or no parental investment
289
In terms of parental behavior, hormones shape what 3 things?
1. initiation of parental behavior
2. maintenance and development of parental behavior
3. termination of parental behavior
290
What kind of animal display an enormous diversity in parental behavior?
birds
291
What kind of parental care if common in bird?
Biparental care - equal parental investments
Biparental care is adaptive
292
Parental behavior of birds
nest building
incubation
feeding
protection
293
What do immature birds require to survive?
continuous food intake
294
Alloparenting
caregiving to offspring that is provided by individuals other than their genetic parents
e.g birds
295
North temperate zone birds; Prolactin -> drives what 3 things in many bird species?
onset, maintenance, and duration of parental behavior
296
California mouse fathers have increased ___ concentrations
prolactin
297
In Florida scrub jays, what does prolactin concentrations correlate with?
the amount of care provided to the offspring
298
Prolactin in Florida jay scrubs
prolactin: breeders > helpers > nonhelpers
299
In Florida jay scrubs, what inhibits prolactin?
Stress (corticosterone)
300
4 factors of maternal behavior in marsupials
1. mammary glands
2. maternal care dominates
3. developmental stage at birth varies between mammalian species
4. marsupials: unreliable habitat, can end pregnancy if harsh conditions occur
301
4 factors of maternal care in eutherian mammals
1. placenta
2. more stable habitat
3. greater developmental stage at birth
4. parental care is rare among mammals
302
3 types of maternal care in eutherian mammals (e.g rats)
1. mother provides food care and shelter to altricial young
2. mother bears precocial young capable of independent activity
3. neither/semi-precocial young
303
What animal is a rare example of biparental care in mammals?
The California mouse
304
Endocrine correlates of mammalian parental behavior (6 hormones)
1. prolactin
2. prostoglandins
3. beta-endorphin
4. oxytocin
5. progesterone
6. several estrogens
305
Concaveation (foster pup rat study)
In rats, foster pups presented to nulliparous female for several hours a day; female begins to behave maternally
sensitization
all behaviors typically observed in rat dams are observed in "sensitized" females, except maternal aggression
also seen in male rats
not hormonally mediated (occurs after ovariectomy; mediated by dopamine?)
306
Maternal Aggression
Serves to protect offspring from predators or intruders
Hormonally regulated
Progesterone
307
(Progesterone & Maternal Aggression)
1. P treatment ___ aggressive behavior in nulliparous mice
2. Pregnant females start to show ___ behavior when P levels peak
3. Pregnancy termination (reduces P) ___ aggressive behavior
4. P replacement ___ behavior in hysterectomized animals.. but aggression is __ after birth when P levels are low
1. elevates
2. aggressive
3. eliminates
4. restores, high
308
Endocrine correlates of maternal behavior in primates
largely unknown
309
Role of experience in maternal behavior in primates?
Hormones help establish onset of maternal behavior in first-time mothers but not necessary to stimulate the behavior in experienced mothers
310
Hormones & basic parental behaviors in humans
hormones are nether necessary nor sufficient for the appearance of basic parental patterns
311
Maternal behavior in humans
1. adoptive parents, siblings, grandparents, caregivers show attachment
2. same behavioral pattern; different endocrine profiles
3. concaveation
312
Oxytocin & role of maternal behavior in humans
Mothers with high O levels show higher gaze with infant or polymorphism
313
Expected human fathers display reduced concentrations of what hormones? Increased circulating concentrations of what hormone?
reduced - T and cortisol
| increased - estradiol
314
What hormone concentration is elevated in fathers just before birth?
Prolactin, like California male mice
315
Men who respond to infant cries show ___ prolactin relative to unresponsive fathers
elevated
316
What hormone is elevated in fathers?
oxytocin
317
What enhances father-child interactions?
intranasal OT
318
Lateral projections from where are critical in rat maternal behavior?
MPOA
319
How does estrogen promote maternal behavior?
By enhancing activity in neural circuit that underlies maternal behavior
320
Neural circuit that underlies maternal behavior
MPOA (hypothalamus), BNST, septum
321
What does lesions to MPOA eliminate in rats?
maternal behavior
322
Maternal care organizes brain of offspring to respond to what?
Environment
| Nongenetic transmission of parenting styles
323
Low maternal licking/grooming in rats:
1. ___ GR in hippocampus
2. ___ HPA stress response
3. Offspring become ___ L&G
1. decreased
2. exaggerated
3. low
324
High maternal licking/grooming in rats:
1. ___ GR in hippocampus
2. ___ HPA stress response
3. Offspring become __ L&G
1. increased
2. efficient
3. high
325
What kind of studies studied nongentic transmission of parenting styles?
cross fostering studies
326
What brain regions were activated in response to seeing picture of own child vs. unrelated?
```
Precuneus
MPFC
OFC
Midbrain
Posterior Cingulate
ACC
Thalamus
DLPFC
Regions associated with motivation, reward, emotion regulation
```
327
Some ___ behaviors evolved from parental behavior
social
328
What two kinds of love evoke similar brain activity?
maternal and romantic
329
Affiliative behaviors
how most primate species communicate affection and reduced group tension
e.g calmly sitting close to each other, touching, mutually grooming, etc
330
Relationship status and oxytocin levels
Couples displaying high interactive reciprocity scores
331
What rating did oxytocin enhance of partner's faces?
attractiveness
332
What brain region activity was enhanced when partner's face was shown? When was it suppressed?
NAcc (reward circuit)
| Suppressed reward circuitry response to unfamiliar face
333
In what species is pair-bonding adaptive?
species whose offspring require biparental care
monogamous
334
What are the proximate means of bringing about cooperation of biparental care/parents staying together?
hormones that evoke affiliation
335
Higher levels of oxytocin binding where in the brain for monogamous?
NAcc, fronto-parietal cortex, lateral amygdala, thalamus
336
Higher levels of oxytocin binding where in polygamous?
Lateral septum
337
Attachment
A strong emotional bond between caregiver and offspring, important for subsequent emotional stability
338
___ antagonist reverses partner preference in females (monogamous praire voles)
oxytocin
339
___ antagonist reverse partner preference in males (monogamous praire voles)
vasopressin
340
Disrupting ___ signaling disrupts social preference in zebra finches
oxytocin
341
What does oxytocin treatment in dogs promote?
social behaviors with other dogs and with human owner
342
Types of Aggression
```
Predatory
Intermale
Fear-induced
Irritable
Territorial
Maternal
Instrumental
Predatory attack
Self-defensive behavior
Parental defensive behavior
Social conflict
```
343
Common lab tests of aggression
```
Muricide (mouse killing) by cats or rats
Shock-elicited fighting
Isolation-induced aggression
Resident-intruder aggression
Maternal aggression
Brain stimulation-induced aggression (hypothalamus)
Dominance-related behavior
Visible burrow stressor
```
344
Seasonal variations in what hormone and what behavior coincide?
T and aggression
345
When do aggressive behaviors increase? Why?
At time of puberty, when the testes become active again and androgens level rise
346
Seasonal changes in aggression may also be mediated by ___ signaling
estrogen
347
What does low T inhibit?
reproductive success
348
What does high T suppress?
immune function/survival
349
How come the hormone-behavior relationship (TAggression) is bidirectional?
Social experience can affect hormone concentrations
350
Males who lose a fight show ___ T levels; how long does this last?
suppressed; many days after defeat (in monkeys this suppression can last for weeks)
351
Winning males in fight had T levels that ___ with 24 hours of victory
quadrupled
352
In males, winner of competition show ___ T, & ___
high
| aggression
353
Androgel
GnRH drug
| Lowers t
