Substances Flashcards
inulin
measures ECF
measures GFR
(131) I- albumin
measures plasma
Evan’s Blue Dye
measures plasma
antipyrene
measures TBW
(2) or (3) H20
heavy water
measures TBW
thiosulfate
measures ECF
Na+ probe
measures ECF
erythropoietin
increase RBC
1-alpha hydroxylase
produces active Vit. D (calcitriol)
renin
converts alpha2 globulin into angiotensin I
bradykinin
vasodilation
PGE2
vasodilate afferent arteriole
increase GFR
NO
vasodilator
increase GFR
endothelin-1
potent vasoconstrictor: constrict afferent and efferent and decrease GFR
produced in endothelial injury
angiotensin II
- vasoconstrictor: reduces GFR and opposes autoregulation
- stimulates aldosterone
- enhances PT Na reabsorption (Na/H antiporter activation)
- augments SNS
- vasopressin secretion
- contraction of mesangial cells which decreases glomerular capillary SA and reduces permeability
binds AT1 and AT2
aldosterone
secreted from adrenal cortex
acts on: principal cells in CD
Na reabsorption, K secretion
MOA: binds to cytoplasmic receptor, moves to nucleus and stimulates NaK-ATPase and stimulates ENac to move Na into cell, lumen becomes negative stimulating ROMK for K secretion
increases: Na/Cl cotransporter; synthesis Kreb enzymes (ATP synthesis); basolateral SA
insulin
degraded by kidney
moves K into cells: stimulates Na/H exchanger (Na into cell) wich in turn stimulates Na/K ATPase
Tx: hyperkalemia
creatinine
measure GFR
10% secretion = overestimates GFR
Para-aminohippurate (PAH)
measure renal plasma flow
filtered and actively secreted (completely in one pass)
carbonic anhydrase
cell: converts H2O + CO2 to H2CO3
lumen: converts H2CO3 to H2O + CO2
parathyroid hormone (PTH)
DCT: conserve Ca
PCT: decreases Na/PO4 cotransporter: increases PO4 excretion
stimulate 1-alphahydroxylase
decreases PTH: Ca, calcitriol, FGF23
increases PTH: high phosphorus, low Ca, FGF23
Natriuretic peptide (ANP)
medullary CD
increase NaCl excretion (renal vessel: dilate afferent and constrict efferent); inhibits reabsorption (tubules); inhibits aldosterone (adrenal cortex)
does not alter K secretion
vasopressin (AVP) or antidiuretic hormone (ADH)
secreted from posterior pituitary
responds to increase plasma osmolality and pressure (ECFV: if severe decrease, overrides plasma osmolarity)
binds V2
inserts urea channels in cells of inner medullary CD to pack more urea into interstitium
V2
receptor on epithelial cells in CD basolateral membrane
cAMP pathway, PKA
inserts aquaporin 2 into luminal membrane of CD
Na
impermeable to cell membrane
urea
permeable to cell membrane
water
permeable to cell membrane
glycerol
slowly permeable to cell membrane
adrenaline/epinephrine
vasoconstrictor: preferential afferent
decrease GFR
moves K into cells: stimulate Na/K ATPase through B receptor
angiotensin converting enzyme (ACE)
cleaves angiotensin I into angiotensin II in kidney and lung
phosphate
urinary buffer for acidic urine
accounts for max H excretion of 10-40 mEq daily
B blocker
impairs hormonal Na/K ATPase: elevated K in ECF
alpha receptor
inhibits Na/K ATPase
bicarbonate
increase K uptake into cell
Tx: hyperkalemia
V1
vascular cells of medulla regulate renal blood flow
AT1
angiontensin II receptor
mediates angiotensin II actions on vessels and renal tubules
calcitonin
Ca into bones
