Endocrine function of the Kidney Flashcards
Primary function of active form of vitamin D
a. Increase absorption of Ca2+ in the intestines
b. Increase renal absorption of Ca2+
c. Increase renal absorption of phosphate
d. Mobilize Ca2+ stored in the bone
A
Calcium binding by distal nephron?
a. Coupling with Na+
b. Regulation with PTH
c. Reabsorption of 25%
d. AOTA
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- Potassium is important in all of the following cellular mechanism with the exception of
A. cell excitability B. cell volume control C. DNA and protein synthesis D. acid base balance regulation E. none of the above
E
- Acute cellular uptake of potassium is enhanced by
A. alpha catecholamines B. hyperosmolality C. insulin D. cell damage E. acidosis
C
- The principal site of renal potassium excretion is the
A. intercalated cells of the medullary collecting duct
B. principal cells of the cortical collecting duct
C. distal convoluted tubular cells
D. connecting segment cells
B
- A hyperkalemic patient with a transtubular potassium gradient of (TTKG) of less than 7.0 is highly suggestive of
A. presence of simple renal hyperkalemia
B. hypoaldosteronism
C. increased ECF volume
D. increased sodium intake
B
- In the thick ascending limb of the loop of Henle, calcium reabsorption is by
A. passive diffusion through transcellular calcium channels
B. Ca-Mg exchange mechanism
C. passive paracellular diffusion
D. Ca-Mg ATPase
C
- Physiologic effects of parathyroid hormone includes
A. reduces GFR and filtered load of calcium
B. inhibits NaHCO3 reabsorption in the proximal tubule
C. increases Ca reabsorption in the distal convoluted tubule
D. all of the above
D
- Majority of plasma phosphate exist
A. in protein bound forms
B. complexed to Ca, Mg and Na
C. as ionized phosphate
D. in equal proportions of the above
A
- Most of the filtered phosphate is reabsorbed in the
A. proximal tubule
B. thin descending limb of the loop of Henle
C. thick ascending limb of the loop of Henle
D. collecting duct
A
What differentiates thedistal tubulefrom theproximal convoluted tubule?
A. presence of Na-K ATPase pump at the basolateral membrane
B. Ca reabsorption at this site is enhanced by the the parathyroid hormone
C. reabsorbed Na diffuses to the peritubular capillaries
D. presence of brush border at the luminal side
B
Magnesium is involved in many biochemical processes in the body. What are the sites of Mg2+ reabsorption? A. PT & Thick Ascending Limb B. Thick & Thin Loop C. CD & PT D. PCT & DT
A
PTH increases plasma Ca2+ concentration by:
A. Increase bone resorption
B. Increase renal Ca2+ absorption
C. Stimulate 1,25-dihidroxy vitamin D3 production
D. All of the above
D
Calcium reabsorption in the nephron is
A. by both paracellular and transcellular routes in the proximal tubule
B. exclusively transcellular in the distal tubule
C. Both of the above
D. Neither of the above
C
Potassium secretion is stimulated by
a. Aldosterone
b. Anti-diuretic hormone
c. Angiotensin II
d. Angiotensin I
A