HYS- CH5.1,5.2 - Endocrine System - ADD MORE Flashcards
endocrine means
to secrete into (hormones)
pancreas history
removing pancreas of dog causes same symtoms of diabetes
hormone derivation
peptide hormones
side chains are polar or charged, hydrophillic, large
cant cross plasma membrane
exert effect on outside. Receptors in exterior of cell membrane. Receptors are part of second messenger systems to relay
quick onsets
short duration
..in ending. means what kind of hormone
peptide
insulin
oxytocin
most hormones with abbreviations (FSH, LH)
steroid hormones
large hydrocarbon ring system thats non polar. steroid proteins often bound to carrier proteins in bloodstream. Once it reaches target cell it can diffuse bc of hydrophobic nature inside. (Diffusion doesnt need membrane protein). Steroid receptors are often intracellular and bind to steroid hormone and as a complex migrates to nucleus to affect transcription
derived from cholsterol. look for “s,t,r” near eachother
- testosterone, estrogen, aldosterone, cortisol
slower to act
last longer
all major glands in head and neck are __ hormones
peptide hormones, derived from amino acids
pituitary gland
anterior - glandular
FLAT PEG are tropic hormones which act on other glands which releases other hormones to act ion target gland
F- FSH on gonads
L - LH on gonads
A - acth
T - TSH on thyroid
**PEG are direct **
P - prolactin
E - endorphins, endogenous opiods
G - HGH
posterior - nervous tissue
ADH/vasopressin - reduces urine output to stimulate water reabsorption in kidney
oxytocin - love, triggers uterine contractions in birth
hypothalamus
above pituitary gland
secretes trophic hormones into hypophyseal portal system bringing hormones to pituitary gland
GnRH –> increaes FSH, LH –> gonads
CRH –> increases acth –> adrenal cortex
TRH –> increases TSH
GHRH –> increases GH
ADH and oxytocins are peptides that have somas in hypothalamus and transported by axons to posterior pituitary
thyroid
TRH –> TSH ( sets metabolic rate) -> T3 and T4 in the thyroid
T3 and T4 are amino acid derivatives but they behave as if steroids bc they are hydrophobic and need carrier proteins in bloodstream, but need membrane transport protein to cross like steroids, also have intracellular receptors
parathyroid
thyroid regulates calcium
it makes calcitonin hormone which DECR plasma calcium levels by stimulating osteoblasts which pulls calcium from blood and desposits into cells
parathyroid makes parathyroid hormone (PTH) which stimulates osteoclast activity causing calcium RELEASE from bones to release into bloodstream for INCREASE in blood stream
parathyroid and thyroid are anagonistic
as blood calcium rises, PTH is decreased
adrenal gland
ad - towards, renal - kidney
on top of the kidneys
**outer cortex - **
**adrenal cortex - **
gluccocorticoids which regulate blood glucose levels, (oids) means steriod
cortisol and cortison reduce inflammation but causes high blood glucose levels
mineralcorticoids which act on minerals (SALTS)
aldosterone promotes sodium reabosorption in the kidney
sex hormones
androgens and estrogens (all steroids)
medulla - epinephrine and norepinephrine
pancreas cell types
alpha - glucagon
beta - insulin
delta - somatostatin
insulin vs glucagon
insulin reduces blood glucose encouraging glucose uptake
glucagon increases blood glucose by promoting glycogen breakdown and gluconeogenesis in the liver
somatostatin
slows digestive track, inhibits effect of growth hormone, insulin, glucagon
of the pancreas
gonads
ovaries and testes
estrogen – > maturation of folliciles in ovary
progesterone –> prepares uterus for implantation
testosterone –> sperm
all hormones produces in gonads are steroids, everyone needs all three
negative feedback
is TRH released by anterior pituitary?
no its released by the PVN of hypothalamus
wich causes releases of TSH acting the thyroid
TSH on thyroid causes release of T3 and T4,
what hormones stimulates FSH and LS
gnRH
gonadotropin releasing hormone
hormones release by posterior pituitary gland– can it synthesize hormones?
ADH and oxytocin
The two hormones released from the posterior pituitary are actually synthesized in the hypothalamus and simply released from the posterior pituitary gland. The posterior pituitary does not synthesize any hormones itself.
what does ADH/vasopression do?
ADH secreted due to low blood volume (via baroreceptors) or increased blood osmolality (osmoreceptors) increases permeability of collecting duct to water
increases reabsorption of water from filtrate in nephron, retains water more
increased blood volume and higher blood pressure
what does oxytocin do?
secreted in childbirth, coordinated contraction of uterine smoothe muscle, promotes milk ejection, positive feedback, bonding behabior
T3 and T4
T3 and T4 differ in the idoine atoms attached to tyrosine
produced in follicular cells of thyroid
reset basal metabolic rate my making energy production more or less efficient by altering utilization of flucose and fatty acts
incr T3, T4 –> inc cell resp, increased protein and fatty acid turn over, speedig up synthesis and deg of these compounds
what is the neg feed back of increased thyroid hormoes
dec TSH and TRH
prevents excessive T3 and T4
hypothyroidism and hyperthyroidism
hypothyroidism - deficiency in iodine or inflammation, LOW thyroid hormones, decreased temp, slowed resp, slowed heart rate, cold intolerance, weight gain
hyperthryoidism - HIGH thyroid hormones, increased ac, increased body temp, increased resp and heart rate, heat intolerance, weight loss, may result from tumor or thyroid overstimulation
cretinism
deficiency in thyroid hormone in kids which causes intellectual disability nd developmental delays
which cells make calcitonin
C cells (parafollicular cells) of the thyroid
calcitonin
DEC plasma calcium levels
calcitonin TONES down calcium levels in blood
- increases calcium excretion from kidneys
- dec calcium absorption from the gut
- incr calcium storage in bones
can be stimulated by high blood calcium levels
how does parathyroid hormone increase abosorptin of calcium in the gut
via vitamin D
parathyroid hormone and phosphorus homeostasis
increases reabsorption of phosphate from bone and reduces reabsorption of phopshate in the kidney (promotes excretion into urine)
net little affect on phosphate
why is calcium important for the body
bone structure and strength, release of NT from neurons, reg of muscle contraction, clotting of blood (calcium is a cofactor)
PTH and vitamin D
PTH (increaes calcium in blood) activates vitamin D which is need for absorption of caclium and phosphate in the gut
