Exam 1 Flashcards
1
Q
Chemical messengers
A
Neurotransmitters, endocrine hormones, neuroendocrine hormones, paracrines, autocrines, cytokines
2
Q
Adrenal medulla and the pituitary gland secrete in response to
A
A neural stimuli
3
Q
Control over the anterior pituitary
A
Hypothalamus
4
Q
Body functions regulated by hormones
A
- Metabolism
- Growth and development
- H2O/ electrolyte balance
- Reproduction
- Behavior
5
Q
Classes of hormones
A
- Protein/ polypeptides
- Steroids
- Tyrosine derivatives (biogenic amines)
6
Q
Protein hormones are stored in
A
Secretory vesicles
7
Q
Steroid hormones
A
Cortisol and aldosterone
8
Q
Examples of tyrosine derivative hormones
A
Dopamine, thyroxine, norepinephrine/epinephrine
9
Q
Classic endocrine glands
A
- Pituitary
- Thyroid
- parathyroid
- Pancreas
- Adrenals
- Gonads
- Placenta
10
Q
Organs or tissue with endocrine function
A
- Brain
- Heart
- Liver
- GI tract
- Kidneys
- Adipose
- Thymus
11
Q
Parts of brain involved with endocrine function
A
Hypothalamus and pineal gland
12
Q
Rapid hormone secretion
A
Adrenal medulla secretion of norepinephrine and epinephrine
13
Q
Slow hormone secretion
A
Pituitary and thyroid hormone secretion
14
Q
Negative feedback prevents
A
Over-activity
15
Q
Negative feedback is variable by
A
Secretory rate and amount of activity in the target tissue
16
Q
Negative feedback regulated by
A
- Gene transcription and translation
- Steps in Processing hormones
- Steps in releasing stored hormones
17
Q
Positive feedback is seen with
A
Surges of hormone
18
Q
Example of positive feedback
A
Luteinizing hormone stimulating ovulation
19
Q
Diurnal secretion
A
Daily or circadian secretion.
Ex: growth hormone
20
Q
Seasonal or circannual secretion
A
The Pineal gland secretes this way.
Ex: melatonin’s effect on reproduction in seasonal breeding
21
Q
Cyclic or periodic variations of secretion
A
Due to changes in neural activity
22
Q
Transport of water soluble hormones
A
Dissolve in plasma, transported to target tissue, diffuse out capillaries and into interstitial fluid, then into target cells
23
Q
Transport of steroid and thyroid hormones
A
Bind to plasma proteins and circulates in the blood. They must dissociate from the protein to diffuse across capillaries and into target tissue
24
Q
Hormonal clearance
A
Removal of a hormone
25
Hormone concentration
Rate of secretion-rate of clearance
26
Metabolic Clearance Rate (MCR)
Rate of disappearance of hormone from plasma
27
Ways hormones can be cleared from plasma
- Metabolic/enzymatic degradation by tissue
- Binding with tissue
- Excretion by liver into bile
- Urinary excretion by kidneys
28
Locations of hormonal receptors
- in/on the surface of the cell membrane
- cell cytoplasm
- cell nucleus
29
Types of cellular receptors
- Ion channel-linked
- G Protein-linked
- enzyme-linked
30
Ca2+—Calmodulin in smooth muscle: contraction occurs when
Myosin is Phosphorylated by activated MLCK
31
Ca2+—calmodulin in smooth muscle: relaxation occurs when
Myosin is Dephosphorylated via myosin phosphatase
32
Adenylyl cyclase-cAMP active state
GTP is bound
33
Adenylyl cyclase-cAMP inactive state
GDP is bound
34
What activates adenylyl cyclase
Alpha subunit—GTP complex
35
Active adenylyl cyclase converts
ATP to cAMP
36
CAMP activates
PKA
37
What inactivates cAMP
Phosphodiesterase
38
What activates phospholipase C
Alpha q subunit—GTP complex
39
Activated phospholipase C catalyzes what reaction
PIP2 — DAG + IP3
40
IP3 causes
Release of CA2+ from ER or SR
41
DAG + Ca2+ activate
PKC
42
Purpose of 2nd messenger systems
Allows hormones that cant cross membrane to affect cell
Signal amplification
43
How do steroid hormones affect genes
Increase protein synthesis
44
Mechanism of how steroid hormones inc protein synthesis
1. Bind to receptor
2. Go to nucleus
3. Bind to DNA — transcrip — mRNA
4. MRNA goes to ribosomes to form protein
45
How do thyroid hormones affect genes
Increase gene transcription in nucleus
46
How thyroid hormone signals gene transcription
- T3/T4 bind to receptor proteins in nucleus
| - after binding to intranuclear receptors they can express control for days-weeks
47
Concentration of hormone at the cell membrane depends on:
1. Rate of secretion
2. Rate of delivery via circulation
3. Rate of degradation
48
Sensitivity of target cell depends on:
1. Number of functional receptors
2. Receptor affinity for hormone
3. Post receptor amplification
4. Abundance of available effector molecules
49
Magnitude of hormone responses depends on
- concentration of hormone
- sensitivity of cells
- number of target cells
50
Duration of hormone response
Duration of hormonal availability
Mode of production of cell response
How quickly the changes begin
51
How long the hormone lasts depends on
Duration, amount secreted and half-life of the hormone
52
Cellular response is produced by
Reversible covalent modifications and genomic changes
53
Examples of genomic changes
- Time it takes to make mRNA
- mRNA half-life
- time to synthesize proteins
- half-life of affected proteins
54
Tests that measure hormones in blood
RIA and ELISA
55
RIA
Measures immunologic, not biology, activity
56
RIA test
Correlates radioactivity to hormone concentration by creating a competition between the hormone and a radioactive labeled hormone on an antibody
57
ELISA
Can measure any protein depending on their specificity of antibodies or sensitivity of enzyme assays
58
Advantages of ELISA
1. No radioactivity
2. Easily automated
3. Cost effective
4. Accurate hormone levels
5. Popular choice in clinical labs
59
Pituitary gland
The master gland
Anterior and Posterior parts
Lies in sella turcica (sphenoid)
60
Anterior Pituitary gland
Comes from Rathke’s pouch (pharygeal epithelium)
Synthesizes and releases 6 peptide hormones
61
Posterior pituitary gland
Outgrowth from hypothalamus
Stores and secretes 2 hormones from the hypothalamus
62
Pars intermedia synthesizes and secretes
Melanocytes Stimulating Hormone (MSH)
63
Hypothalamus controls
All pituitary secretion hormonally (AP) or neurally (PP)
64
Hypothalamic-Hypophysial Portal system (HHPS)
Releasing and inhibitory hormones secreted into median eminence to control anterior pituitary secretion
65
Hypothalamic Peptide Hormones
TRH, CRH, GHRH, GnRH, Prolactin inhibitory hormone, growth hormone inhibitory hormone, Ghrelin
66
Anterior Pituitary Hormones
1. Growth Hormone
2. TSH
3. ACTH
4. Prolactin
5. FSH
6. LH
67
Posterior pituitary hormones
1. Antidiuretic hormone (vasopressin)
| 2. Oxytocin
68
Growth hormone AKA
Somatotropin
69
TSH is secreted by
Thyrotropes
70
TSH increases
1. Proteolysis of thyroglobulin
2. Activity of iodide pump
3. Iodination of tyrosine (form T3/T4)
4. Size, number, and secretory activity of thyroid cells
71
TSH inhibited by
T3 and T4
72
TSH stimulated by
TRH and cold
73
Adrenocorticotropic hormone (ACTH) stimulates
Cortisol and adrenal androgens secretion
74
ACTH secreted by
Corticotropes
75
ACTH stimulated by
1. Hypothalamic corticotropin releasing hormone (CRH)
| 2. Physical or mental stress/ pain
76
ACTH inhibited by
Cortisol (negative feedback)
77
Prolactin is inhibited by
Hypothalamic dopamine
AKA Prolactin inhibitory hormone
78
Stimulates milk secretion and production and inhibits ovulation
Prolactin
79
Excess prolactin
1. Destruction of hypothalamus or prolactinomas
2. Galactorrhea
3. Infertility
80
Bromocriptine
Treatment for excess prolactin
81
Prolactin _______ aspects of immune response
Enhances
82
FSH and LH are secreted by
Gonadotropes
83
Functions of FSH and LH
1. Stimulate development of ovarian follicles
2. Regulates spermatogenesis
3. Causes ovulation (LH) and formation of corpus luteum
4. Stimulate production of estrogen/progesterone (Female) and testosterone (male)
84
Activin and Inhibin
Dimer protein complexes in gonads, pituitary, placenta and other organs
85
Enhances FSH synthesis and secretion
Activin
86
Helps regulate menstural cycle
Activin
87
_______ inhibits FSH synthesis and secretion
Inhibin
88
Posterior pituitary hormones
ADH and oxytocin
89
Produces milk “letdown” from lactating breast and stimulates uterine contraction
Oxytocin
90
Oxytocin released in response to
Suckling or conditioned responses (sight, sound, or smell of infant)
Dilation of cervix or orgasm
91
Uses of oxytocin
Induce labor and reduce postpartum bleeding
92
Oxytocin inhibited by
Opioids
93
Oxytocin effects on brain
Relaxation, fearlessness, bonding, contentment
Activated by daily closeness and touch
94
Melatonin produced by
Pineal gland
95
Melatonin controls
Reproductive cycle in season breeders , enhances immune function, enhances slow wave sleep
96
Melatonin released
In circadian cycle (mostly during dark phase)
97
Hormones synthesized and secreted by liver
1. Insulin-like growth factor-1 (IGF-1)
2. Angiotensinogen
3. Thrombopoietin
4. Hepcidin
5. Betatrophin
98
IGF-1
Mediates effects of growth hormone
AKA somatomedin C
99
Angiotensinogen
Precursor of angiotensin I and II
100
Thrombopoietin
Stimulates production of platelets
Also produced by kidneys
101
Hepcidin
Key regulator of entry of iron into cells
102
Betatrophin
Promotes pancreatic beta cell proliferation
Also produced by adipose
103
Steroid hormones are conjugated by the _______ and excreted in ______
Conjugated by liver
Excreted in bile
104
Most common cause of death and stability in young people
Traumatic brain injury
105
_____ dysfunction common following TBI
Pituitary
106
Pituitary dysfunction
Most common in GH or FSH/LH
107
GH deficiency
Inability to concentrate, memory problems, anxiety, and fatigue
108
LH/ FSH deficiency associated with
Hypogonadism
109
Central diabetes insipidus
Low ADH
