Endo II Flashcards
ADH
synthesized supraoptic nuclei
-released posterior pituitary
V2 receptor
for ADH - regulate serum osmolarity
mutation - nephrogenic DI
V1 receptor
for ADH - regulate blood pressure
nephrogenic DI
mutation V2 receptor
central DI
ADH level decreased
cholesterol desmolase
stimulated by ACTH
-convert cholesterol to pregnenolone
pregnenolone - start substrate for adrenal steroids
ketoconazole
inhibit cholesterol desmolase
less cholesterol to pregnenolole
17a hydroxylase deficiency
excess aldosterone
- low cortisol
- low sex hormones
increase BP and hypoK - aldosterone effect
decreased androstenedione
boy with 17a hydroxylase deficiency
ambiguous genitalia
undescended testicles
HTN, hypoK
girl with 17a hydroxylase deficiency
lack secondary sex development
HTN, hypoK
21 hydroxylase deficiency
low aldosterone
- low cortisol
- hgh sex hormone
decreased BP and hyperK - lack of aldosterone
labs - increased renin and increased 17-hydroxyprogesterone
MC
girl with 21 hydroxylase deficiency
virilization and precocious puberty
low BP and hyper K - low aldosterone
low cortisol
11-B hydroxylase deficiency
low aldosterone - but elevated 11-deoxycorticosterone (weak mineralocorticoid)
decreased cortisol
increased sex hormone
HTN and hypoK
decreased renin activity
girl with 11-B hydroxylase deficiency
virilization
aromatase
convert testosterone > estrogen
5-a reductase
convert testosterone > DHT
reactivation of TB and candida
exogenous corticosteroids
block IL-2 production
cortisol activity
upregulate a1 receptors - HTN increased insulin resistance gluconeogenesis, lipolysis, proteolysis striae - decreased fibroblasts decreased inflammation decreased bone formation
plasma Ca
majority ionized
bound to albumin and anions also
increased pH
more affinity of albumin - more negative charge
-to bind Ca
get hypoCa - cramp, pain, paresthesia
cholecalciferol
Vit D
D3 from sun exposure
D2 ingested from plants
function of vit D
increased absorption of diet Ca and P
increased bone resorption - Ca and P increase
24,25 D
- inactive storage vit D
kidney and vit D
1-a hydroxylase - convert 25 to 1,25 (active)
negative feedback of 1,25 on its production
PTH
increased Ca reabsorption
decreased P reabsorption
in kidney
1,25 Vit D
increased absorption Ca and P
in gut
PTH
from chief cells of PTH
PTH in kidney
more Ca reabsorption - DCT
less P reabsorption - PCT
1-a hydroxylase
convert 25 D > 1,25 D
stimulated by PTH
-synthesized PCT
PTH on bone
production of m-CSF and RANKL
RANK-L - secreted by osteoblasts - binds RANK on osteoclasts
-stimulate osteoclast activity
sort of low Mg
stimulate PTH release
very low Mg
inhibit PTH release
calcitonin
from parafollicular C cells of thyroid
decrease bone resorption of Ca
hormones act through cAMP
FSH LH ACTH TSH CRH hCG ADH - V2 MSHR PTH calcitonin GHRH glugacon
hormones act through cGMP
ANP
BNP
NO
hormones act through IP3
GnRH oxytocin ADH - V1 TRH histamine - H1 ANG II gastrin
hormone act through intrinsic tyrosine kinase
insulin IGF-1 FGF PDGF EGF
MAP kinase - growth factors
hormone act through receptor associated tyrosine kinase
PRL GH G-CSF EPO thrombopoietin
JAK/STAT - acidophils and cytokines
steroid hormones
circulate bound to binding globulin
-increase their solubility
SHBG
sex hormone binding globulin
men - lower free T
women - decreased raises free T - hirsutism
women - increased with OCP, pregnancy - free estrogen levels remain unchanged
