Endocrine Flashcards
(51 cards)
primary damage:
damage to the endocrine gland
secondary damage
damage to pituitary or thalamus
primary glands
only job is hormone secretion
- pineal, hypothalamus, pituitary, parathyroid, thymus, adrenals, ovaries, testes
autocrine signalling
cell releases a hormone—> targets the same cell to make more molecules ( local)
paracrine signalling
1 cell secretes hormones that interacts w neighbouring cells to influence their activity
ex: ecosinoids
secondary hormones:
heart–> ANP
Kidneys__> bicarb, erythropoiten,
cortisol, ALDO, E/P/T are examples of ….
steroid hormones
- hydrophobic molecules
can diffuse across cells membranes to transcript MRNA
glycoproteins, AA derivaties, and ionated AA=
nonsteriodal hormones
upregulation
when there is a decreased amount of hormone in the blood the target ell will make more receptors to pick up more hormones
down regulations
when there is too much hormones in the blood and the target cells reduce its amount of receptors to take up less hormone
neurohypophysis secretes…..
vasopression, oxytocin
adenohypophysis secretes…
TRH, CRH, TSH, ACTH, LH & GNRH, prolactin, somatostatin
short loop feedback:
when the pituitary hormone changes the secretion of the hypothalamic hormone
long loop feedback
target organ changes the hormone secretion of the hypothalamic/pituitary hormones
circadian rhythms….
influences the production of CRH in blood
GH=++ secretion @ 12am–>4am
adrenal cortex layers
zona glomerulosa: outermost, secretes mineralcorticoids ex:ALDO
Zona fasiculata: middle zone which secretes glucocorticoids, ex: cortisol
ZOna reticularis: inner most layer that secretes gonadococorticoidsex:androgens
adrenal medulla secretes…
catechoalmines like norepinephrine
ALDO functions:
regulates ECF fluid vol by reabsorbing Na+ & H2O in the nephron of the kidneys
-regulates ECF K+ Na+/K+
- release stimmed by ++ANG2 when Bp= low–> travels through caps & diffuse through nephrons cells—>bids to cell receptor & alters mrna transcription to ++ expression of NA+/K+ pumps= more K+ excreted +Na+ reabsorbed
glucocorticoid functions:
+BGL, aa/FA , gluconeogenesis, anti-inflammatory
neg feedback loop for hypothalamic- pituitary pathway:
1 hypothalamus = stimmed by stress/circadian rhythm–>anteiror pituitary–> secretes acth (influencescells of zona fasiculata to secrete more cortisol
(as CRH increases—> cortisol +/as Cortisol +—> CRH decreases)
cushings diease
primary/secondary hypercortisol secretion, onset=40yrs, can be iatrogenic due to excessive use of glucocorticoids & can completely stop the production of CRH/ACTH
s/s:Fat depositions, Decreased muscle mass: muscle weakness
Bone demineralization
aldosterone(like effects)
Increased production of androgens
Hyperglycemia ( loss of sensitivity to insulin)
Poor concentration & memory
Addisons disease
primary hypocortiso; secretion & low ALDO, hypovolemia, hyponatremia, hyperkalemia, decreases BGL, N/V/D/C, +pigmentation
general adaption syndrome (GAS)
1) ALARM: stress activity of hypothalamus ++ cotrisol/+SNS, 2)resistance–> maintenance of alarms, allostasis, if stress not managed body compensates( counter productive) 3) exhaustation: body resources are depleted ++ risk of infection
thyroid hormone fucntions…
T3/T4–> ++ SNS response
- ++BMR, +protein synthesis/degradation, glycogenolysis, gluconeogenesis, + lypolysis, +Hr/FOC/CO