Exam 3 Flashcards
What happens once insulin is released from pancreas?
- it is degraded primarily by the liver during the first cycle through (up to 80% if not utilized)
- kidney and target tissue decrease levels of circulating insulin
Acetylcholamine (ACH)
- major neurotransmitter between the pre-synaptic neurons and post-synaptic neurons
Epinephrine and Norepinephrine affect on metabolic rate
- Start break down of glycogen quickly
- Make available glucose into 2-pyruvate
- Go through the Citric Acid Cycle
- Make lots of ATP
- Drives physiological processes!
CRH (corticotropin releasing hormone)
- produced by trophoblast (both layers)
- increases through pregnancy
- at level of developing fetus maintains placental blood flow
Molecules and Enzyme Pathway to make catecholamines
- Tyrosine
- tyrosine hydroxylase - DOPA
- DOPA decarboxylase - Dopamine
- Dopamine B-hydroxylase - Epinephrine
- Norepinephrine
GLUT Channels
- glucose channels/transporters
- 14 different types
- GLUT 1-5 are well characterized only
- sodium and ATP independent
- ubiquitous (wide spread throughout mammalian species)
Estrous Synchronization protocols
- Assess the Animals
- BCS (5) and days post-partum (45-50d) - Resources
- labor, facilities, experience, budget
- time for heat detection and what is realistically manageable
Organs of female repro tract
- ovaries, uterus, fallopian tubes, breasts, cervix, uterus and mammary glands (reservoir for milk during lactation)
- ovary is the PRIMARY reproductive organ
- ovaries not connected
- fimbria will capture release of oocyte
- implantation will occur in uterine body or uterine horn
- mullerian ducts derived from mesoderm
Activin in male
- inhibits Inhibin B
- activates FSH and LH release (stimulatory effect)
Glucagon
- glucagon going in opposite direction of insulin (breaks down glycogen to glucose for use)
- helping to utilize what is being stored and put back into blood stream
- high blood glucose levels will inhibit production of glucagon
- fasting state
Nitric Oxide in male
- cyclic GMP inhibits prolonged erections
- penile erection is vasodilation and increased blood flow
What peripheral nervous system will override the other?
- the sympathetic nervous system will override the parasympathetic nervous system
Insulin Receptors
- is a heterotetramer, 2 alpha and 2 beta subunits
- beta subunits bound to the membrane
- alpha are extracellular
- when insulin binds gets cross-phosphorylation and get a downstream intracellular signaling mechanism
- entire receptor complex can be internalized and insulin can be broken down and receptors can be put back on surface of the cell
Norepinephrine affect on the heart
- Norepinephrine binds to receptors on the blood vessels
- causes inc rate and force of heart by vasoconstriction of the blood vessels (dec size) to increase blood pressure
- it is a potent vasoconstrictor
- BUT it can also cause vasodilation by increasing the blood vessel to get more blood flow to target tissue
- > different effects if binds to a different receptor
Estrous Synchronization
- a reproductive management tool to stimulate artificial insemination
- used for a group of females to achieve parturition
- > dec labor and calving period
- > reduce time required for estrus detection (heat)
- use exogenous hormones to manipulate the estrus cycle so all the females come into estrus at once and will ovulate at the same time
- use artificial insemination to improve genetics, guarantee a certain sex, dec number of bulls used
GLUT 1
- blood, blood brain barrier, heart
- insulin independent
Female Reproductive System Function
- to provide ova for fertilization
- to provide proper conditions for implantation, fetal growth, development, birth and lactation
Functions of melatonin
- circadian rhythm (24 hr cycle of light and dark)
- seasonal reproduction
- cardiovascular system
Endocrine regulation of female reproductive tract regulated by
- hypothalamic pituitary gonadal axis
Insulin Functions
- Ensures that excess nutrients are stored
- Decreases blood glucose concentration by limiting the rise in blood glucose after eating
- Promotes the formation of glycogen (storage form of glucose)
- Inhibits glycogenolysis
- Inhibits gluconeogenesis
- Decrease blood fatty acids by inhibiting mobilization of fatty acids and increasing their storage
- Inhibits lipolysis
- Decreases blood amino acid concentration by promoting anabolism of proteins
GLUT 2
- liver, pancreas, SI
- insulin independent
- Km High
Leptin in male
- produced by adipose tissue and linked to increase levels of LH
- males with low adipose have delayed onset of puberty
- people w more adipose can mature earlier (fatties)
Testosterone and Testosterone derived estrogen in male
- LH drives testosterone production
- required for growth spurts in developing males
- inc bone mass and inc bone proliferation
- inc protein synthesis and dec protein breakdown (accum more skeletal muscle mass)
- inhibits lipid uptake and stim lipolysis (aids burn fat)
Physiological Effects of Epinephrine and Norepinephrine
- they bind to their receptors which are classified as adrenergic receptors
- adrenergic receptors are a subclass of G-protein associated receptors
- alpha 1 (increases Calcium)
- alpha 2 (dec cAMP)
- Beta 1 (inc cAMP)
- Beta 2 (inc cAMP)
- > a1, a2,B1 all binds to epinephrine and norepinephrine
- > B2 primarily binds to epinephrine
Adrenal Medulla
- extension of sympathetic nervous system (no connection to parasympathetic nervous system)
Insulin Secretion using GLUT-2 Channel
Mechanism using GLUT-2 channels and high levels of glucose in blood stream to stimulate the release of insulin following a meal
- increase in blood glucose levels stimulates the B cells from the Islets of Langerhans to produce insulin
2.Glucose is transported inside of the cell through the GLUT-2 channel - In the presence of an enzyme glucose becomes Glucose-6-phosphate
- Gluc-6-phos undergoes glycolysis and produces two
3-C glucose - Moves into mitochondria and produces ATP
- ATP has a negative affect on ATP potassium (K+) dependent channels and close them
- Stimulates the insertion of calcium channels
- less K+ being moved in and out of cell - calcium in the blood stream flows into the B-cell
- As calcium moves into the cell, the ER releases the intracellular calcium it was storing
- Calcium influx causes secretory granules containing biologically active insulin + c-peptide fragments to be translocated to the membrane and released into the blood stream
Oral Contraceptive Types
- Combination
- uses combination of Estrogen and Prog for 21 d, off for 7d and back on again - Progestin only
- progestin only synth form of progesterone - Extended Release Contraceptive
- take less often bc lasts longer - Patches/Injections
- to prevent cycle all together, until removed - IUD
- modifies endometrial lining and prevents implantation - Barrier Method
- kills sperm - Morning after
- massive anti-progesterone pills to stop implantation
3 Regions of the Pancreas
- Head
- Body
- Tail
Epinephrine and Norepinephrine affect on the lungs
- bronchioles (where O2/CO2 exchange occurs) have the ability to increase the pulmonary ventilation by dilating the bronchioles
- allows more room for air flow
- The ribcage (skeletal muscle) will be able to open up even more and be able to expand the air you can take in and compress out
- > opens up airways in flight/fight response (stress)
Tyrosine
- a precursor for dopamine, epinephrine and norepinephrine
- produced as a result of ACH being released as a precursor from the sympathetic neurons
Norepinephrine Levels Purpose (normal and abnormal)
- Normal
- execution, memory recall, perseverance - Abnormal
- hesitation, obsession, constant doubt
Female cycle (ovary)
- pituitary hormone targets the ovary
- cycle happens at ovary and causes cycle at uterus
1. Follicular phase - 0 to 14 days
- estrogen increases, progesterone inc
- follicle size increases
2. Ovulation - day 14
- follicle ovulates/ruptures and becomes corpus luteum and produce progesterone
- if oocyte released at ovulation has been fertilized(prego) CL will maintain its size and progesterone will stay high to maintain pregnancy, until implantation of fetus can prod P4 itself and then CL will regress
3. Luteal Phase - 14-28 days
- progesterone starts very high and as regresses dec
- follicle regresses
Glucose
- is hydrophilic
- need channels to move glucose molecules
- glucose transporters present in diff types of tissues
- GLUT and SGLT
- only GLUT-4 is insulin dependent
Normal Dopamine Level Effects
- will spike in levels upon orgasm
- increase immune system
- increases concentration
- boosts mood
- self rewarding
Male and Female ducts are derived from?
- the embryonic mesoderm
Melatonin affect on Long day vs short day breeders
- Long day breeders (spring, more light)
- mares
- dec melatonin, inc GnRH, inc FSH and LH - Short Day breeders (fall, more darker hours)
- sheep, goat
- inc melatonin, dec GnRH, dec FSH and LH
Sertoli cells in male
- develop at week 6
- produce sperm, activin, inhibin, and ABP (androgen binding protein)
- inside the seminiferous tubules
Epinephrine and Norepinephrine Directly Affects
- Heart
- Blood vessels/flow
- Lungs/Rib cage
- Lipids in blood stream
- Metabolic Rate
- Pupils
- Nonessential processes
Islets of Langerhans
- endocrine function of pancreas
- spread throughout entire region, but only makes up less than 3% of total mass
- receive massive amounts of blood flow, 15-20% of blood flow going to pancreas goes here
- contains alpha and beta cells
- contains fenestrated capillaries
- is innervated by sympathetic and parasympathetic neurons
FSH and LH
- released from blood stream and targets the ovary
Leydig cells in male
- develop at week 9
- produce testosterone, androstenedione and DHEA(prod test and estr)
What happens when sperm and egg fuse?
- haploid cells become diploid and keep going through cell division
- migrating during cell division
- form morula compacts to blastocyst
- blastocyst implants
- blastocyst breaks down the uterine wall and implant, when it does 3 germ cell layers develop and CNS will form
- from germ cell layers and CNS everything else develops
- complete within 90 days CL regress, fetus self sustains, placenta forms
2 Functions when dealing w Pancreas and Endocrine Function
- Well Fed
- Fasting
- > food for fuel or you don’t
What is the Peripheral Nervous System (PNS) consist of:
- Parasympathetic Nervous System (PNS)
- rest and digest
- feed and breed - Sympathetic Nervous System
- flight or fight
- quicker response
GLUT-2
- located on liver, pancreas and basal side of small intestine
- insulin independent, responds to levels of glucose
- high Km and a low affinity
- bidirectional
- present when have high levels of blood glucose
How do sperm penetrate oocyte
- sperm undergo capacitation, acrosomal reaction
- have to get through zona pellucida (leaves tail in layer
Abnormal Epinephrine and Norepinephrine Levels Effects
- Excess
- excess sweating, inc blood pressure, headache, anxiety, tremors - Deficient
- inability to deal with stress
Epinephrine Specific Function
- satisfaction (ok im cool w that)
Diabetes insipidus
- have normal blood glucose, nothing to do with glucagon or insulin, pancreas not involved
- has to do with ADH (antidiuretic hormone)/AVP (argenine vasopressin) at level of nephron
- indiv had similar symptoms to diabetes mellitus
FSH and LH in females
- targets developing oocyte
- FSH binds granulosa cells heavily and theca cells a little
- LH binds heavily to thecal cells, but lightly to granulosa cells
- increases level of estrogen
- during ovarian phase FSH targets developing oocyte and grow (up regulation of LH receptors)
- but then LH spikes causes ovulation (oocyte released)
Insulin in pancreas
- insulin helps store glycogen!
- helps in the storage of fatty acids and convert to triglycerides for long term storage of glycogen
- will stimulate lipogenesis and inhibits lipolysis
- high blood glucose levels will stimulate production of insulin
- well fed state
- insulin will trump glucagon!
GLUT-4
- not bidirectional
- located on skeletal muscle, adipose and the heart
- insulin dependent
- exercise will increases the presence of GLUT-4
Mechanism to store glucose in glycogen structure
- in presence of hexokinase which is in most cells, begin process of storing glucose as glycogen (rate limiting step)
1. Glucose - hexokinase
2. Glucose-6-Phosphate - mutase
3. Glucose-1-Phosphate
4. Uridine diphosphate glucose - glycogen synthase
5. Glycogen - glycogenphosphorylase (reverse process down)
6. Glucose-1-Phosphate - mutase
7. Glucose-6-Phosphate - glucose-6-phosphatase
8. Glucose - > in a well fed state can move glucose out of blood stream into cell
- > reverse process from glycogen back to an energy source need glucose-6-phosphatase, but only present in some tissue
ABP (androgen binding protein)
- is primarily in the testes
- synthesis in sertoli cells
- bind to testosterone and preserve half life
Dopamine Specific Function
- mood
- self rewarding (that was great lets do it again!)
Pathway to Production of the Catecholamines
- CNS, specifically the pre-ganglionic neurons, are stimulated by sympathetic nervous system neurons to release acetylcholine (ACH) into adrenal medulla
- Presence of ACH in the adrenal medulla drives the production of tyrosine
- Tyrosine will convert to DOPA then the catecholamines in the presence of enzymes
Epinephrine and Norepinephrine affect on Nonessential Processes
- when epinephrine/neuroepinephrine pathway is fully activated through sympathetic nervous system it will inhibit all nonessential processes
- this includes breeding, digesting, relaxing, etc
- > dec of blood flow to target organs, but enough blood flow to survive