(27-2) Pituitary Hormones Continued Flashcards
1
Q
(Prolactin)
- secreted as what?
- major target organ?
- receptors on most tissues?
- synthesized/secreted by many or one tissues?
- role in transition to sexual maturity in rats
- required for pregnancy maintenance in dogs, rodents, and skunks
A
- prohormone
- mammary gland
- yes
- many
2
Q
(Prolactin)
- influence what kind of behaviors?
- suppresses what?
- growth support of what?
- stimulatino of what?
- marked effects on what?
A
- parenting
- lipid storage
- pancreatic islets
- insulin
- immune function
3
Q
(Prolactin Stimulation)
activation - TRH
inhibition - Doopamine
A
4
Q
(Prolactin Control)
- Tonic suppression of Prl by what?
- What is main inhibiting factor? another? feedback?
- What are stimulating factors?
- What is secreted during late pregnancy that stimulates Prl? prepare for what?
A
- Hypothalamus
- dopamine; somatostatin; negative
- TRH, GnRH, stress, sucklking
- estrogens; parturition
5
Q
(Where does dopamine come from)
- what in the HT?
- some dopaminergic neurons in the what that connect via what?
- Non lactotroph cells of the AP secrete a small amount of DP that diffuses to the lactotrophs and inhbits prl secretion by a what mechanism?
A
- dopaminergic neurons in HT
- posterior pituitary; short portal veins
- paracrine
6
Q
(Prolactin: Major effects)
- What does it do?
A
- mammary gland development, milk production and reproduction
just read these
pay extra atention to GnRH on end of list (need to resources for developing milk and not developing fetus - won’t get preggers while lactating)
7
Q
(SHIFTING TO POSTERIOR PITUITARY)
learn this
A
8
Q
only differ by a couple AA’s
A
9
Q
learn this (figure from text book)
A
10
Q
(Antidiuretic Hormone aka ADH aka Vasopressin)
- ADH is a how many AA peptide?
- Within hypothalamic neurons, the hormone is pacakged in secretory vesicles with a carrier protein called what? Both are released up what?
- Major effect in on what (regulates what)?
- Major role?
A
- 9 AA
- neurophysin; hormone secretion
- kidney (fulid osmolarity)
- water conservation
11
Q
(Antidiuretic Hormone aka ADH aka Vasopressin)
- diuretic does what?
(Effects on Vascular systems of ADH)
- high conc of ADH cause widespread constriction or opposite of arterioles? leads to what?
A
- increases rate of urine formation
- constriction; increased arterial pressure (why vasopressin was coined)
12
Q
(Actions of ADH)
- ADH binds to receptors in what of kidny?
- promotes what?
- In absence of ADH, kidney tubules are what?
- big thing it does then?
A
- distal or collecting tubules of kidney
- reabsorption of water back into circulation
- impermeable to urine
- increase in water permeability
13
Q
(Actions of Antidiuretic Hormone)
- ADH receptor is coupled to a IP#/Ca2+ messenger system which results in what?
- Increae in vascular resistance causes increase in what?
- When is ADH released?
A
- contraction of vascular smooth muscle (constriction of arterioles and increased peripheral resistance)
- blood pressure
- when dehydrated (increased osmolarity)
14
Q
(ADH)
- What are inserted into membranes of kidney tubules to move water?
A
- aquaporins
15
Q
(control of ADH)
- main variable which regulates ADH is what?
- osmolarity sensed by what?
- What stimulate secretion of ADH?
- When osmolarity is below a threshold, osmoreceptors are what? What is suppressed?
A
- plasma osmolarity
- osmoreceptors (HT neurons)
- neurons
- osmoreceptors are not active - ADH is suppressed
look at this
ECF = extracellular fluid
16
Q
(pathophysiology of ADH)
- What is it called when there is a definiency in ADH secretion from posterior pituitary?
- occurence in catas and gods?
- what is it called wh kidney is unable to respond to ADH? ADH concentrations high or low? typically due to what?
- signs (of both)?
A
- Diabete insipidus (large amts of dilute urine and body fluid become concentrated)
- rare
- nephrogenic diabetes insipidus; high (due to simulation by icreased serum osmolarity); renal disease
- excessive thirst; PU/PD
