endo physio Flashcards
GnRH pathway
+ FSH & LH
>gonads
F- estrogen + progesteron
M- testosterone
GHRH pathway
+GH
>prot synth + metab
SS pathway
- GH
>inhib prot synth and metab
TRH pathway
+TSH
>secr T3 and T4
DA pathway
-prolactin
>breast development and milk production
CRH pathway
+ACTH
> secretes cortisol in adrenal
h-pit-thy axis
stimuli > hypo-trh > ap-tsh >
thy-t3 & t4 > inhib abv
target cells
iodine trap
controlled by tsh and nak atpase agaisnt conc and elect gradient
ACTIVE extraction and conservation of the small amount of i from the blood in the colloid
steps of thy h prod totc
i trapped
memb bound peroxidase convert iodide to iodine (reactive form)
thyroglob synthesized
oxid coupling > iodine binds to tyrosine to form t3 or t4 (mostly 4)
totc - trap-oxid-thyrglob-coupling
pinocytosis
colloid droplets enter follicular cells containing the trapped i
exocytosis
uniondinated thyroglob passes from follicular cell to colloid
proteolysis
proteolytic degradation of thyroglob
t3 and t4 transp in blood
mostly tbg
tbpa - low aff for t4 no aff for t3
albumin
thy h effects on heat
inc o2 consump and heat prod
adaptation to cold environ
calorigenesis
t3 and t4 affects on post natal devel
def leads to dec prot synth, myelinogen and retarded axonal ramification
> irreversible compromised - cretinism
cretinism
congen iod def synd
t3 and t4 affects on gh
gh sec is red by absence of thy h
def in thy h > red in gh action because of permissive effect
dwarfism
thy h affects on carb metab
inc hepatic glycogenolysis
inc abs of gluc
directly break down insulin
lipolytic to inc glucose
incretins defn and role
gut hormones secr minutes after eating that reg insulin secr
glp and gip
rapidly deactivated by enzyme dpp 4
whipples triad
symptoms of hypoglycemia
documented hypoglycemia during symptoms
prompt reversal of symptoms with restoration of euglycaemia
specific tube for blood glucose sample
fluoride citrate tube that contains enzyme thst stops glycolysis within the sample
cortisol physio role
stress h
forms gluc from non carb
maintains glycogen reserves
inc blood gluc
in hep gluconeogenesis
anti insulin affect
deaminates aa to yield glucose
excess cortisol affect on prot metab
prot catab inc
inhibs uptake and prot synth
result in severe muscle wasting
effects of cortisol on lipid metab
promotes lypolysis
generates ffa for gluconeogenesis