Practice Questions Flashcards
Which of the following is most likely to produce an increase in GFR in patients with acute renal failure?
A. administration of angiotensin II
B. contraction of glomerular mesangial cells
C. dilation of afferent arterioles
D. increased renin release from the JG apparatus
E. volume depletion
C. dilation of afferent arterioles
Substance X is injected into an arterial line to assess its renal handling. All of substance X appears in the urine and none is detected in the renal vein. What do these findings indicate about the renal handling of substance X?
a. it must be filtered by the kidney
b. it must be reabsorbed by the kidney
c. its clearance must be equal to GFR
d. its clearance is equal to RPF
e. its urinary concentration must be higher than its plasma concentration
d. its clearance is equal to RPF
Aldosterone secretion is increased when there is a decrease in which of the following?
a. ACTH
b. Angiotensin II
c. Potassium
d. Renin
e. Sodium
e. Sodium
Which of the following statements concerning normal renal handling of proteins is correct?
a. Proteins are more likely to be filtered if they are negatively charged
b. Proteins can be filtered and secreted but not reabsorbed by the kidney
c. Most of the proteins excreted each day is derived from tubular secretion
d. Protein excretion is directly related to plasma protein concentration
e. Protein excretion is increased by sympathetic stimulation of the kidney
e. Protein excretion is increased by sympathetic stimulation of the kidney
A 92 y/o male presents with dehydration following 4 days of persistent diarrhea. Under this circumstance, hypotonic fluid would be expected in which of the following?
a. Glomerular filtrate
b. Proximal tubule
c. Ascending limb of the loop of Henle
d. Cortical collecting tubule
e. Distal collecting duct
c. Ascending limb of loop of henle
Which of the following statements best describes the action or secretion of renin?
a. converts angiotensin I to angiotensin II
b. converts angiotensinogen to angiotensin I
c. it is secreted by cells of the proximal tubule
d. its secretion is stimulated by increased mean renal arterial pressure
e. its secretion leads to loss of sodium and water from plasma
b. it converts angiotensinogen to angiotensin I
The effect of decreasing the resistance of the afferent arteriole in the glomerulus of the kidney is to decrease which of the following aspects of renal function?
a. filtration fraction
b. GFR
c. oncotic pressure of peritubular capillary fluid
d. renal plasma flow
e. renin release from JG cells
e. renin release from JG cells
A 36 y/o man presents with low renin essential HTN. Renin release from the JG apparatus is normally inhibited by which of the following?
a. aldosterone
b. beta-adrenergic agonists
c. increased pressure within the afferent arterioles
d. prostaglandins
e. stimulation of the macula densa
c. increased pressure within the afferent arterioles
A 58 y/o male is hospitalized following an acute MI. Several days later, the patient’s 24 hour urine output is lower than normal. An increase in which of the following contributes to a reduced urine flow in a patient with CHF and reduced effective circulating volume?
a. ANP
b. Renal natriuretic peptide (urodilatin)
c. Renal perfusion pressure
d. Renal sympathetic nerve activity
e. Sodium delivery to the macula densa
d. Renal sympathetic nerve activity
[an increase in renal sympathetic nerve activity promotes a decrease in NaCl and water excretion by decreasing GFR, increasing renin secretion, and increasing tubular NaCl reabsorption]
A 58 y/o man presents with hematuria, abdominal pain and fatigue. Physical exam reveals a flank mass on the left kidney. Lab studies show anemia and increase creatinine and BUN suggestive of advanced disease. A decrease in GFR would result from which of the following?
a. Decrease in concentration of plasma protein
b. Increase in afferent arteriolar pressure
c. Increase in RBF
d. Compression of the renal capsule
e. Constriction of the efferent arteriole
d. Compression of the renal capsule
Renal and pulmonary biopsies in a 35 y/o woman with Wegner’s granulomatosis demonstrate glomerulonephritis and a granulomatous vasculitis in the lungs. In adults, which of the following is greater in the pulmonary circulation compared to the renal circulation?
a. Arterial pressure
b. Blood flow
c. Capillary hydrostatic pressure
d. Capillary oncotic pressure
e. Vascular resistance
b. Blood flow
A hypertensive patient develops chronic renal failure from progressive nephrosclerosis. Which of the following is associated with chronic renal failure?
a. A decrease in the excretion of creatinine
b. A decrease in the fractional excretion of sodium
c. A decrease in net acid excretion
d. An increase in free water clearance
e. A normal anion gap
a. A decrease in excretion of creatinine
ADH conserves water by
A. Constricting afferent arterioles, thereby reducing the GFR
B. Increasing water reabsorption by the PCT
C. Stimulating active reabsorption of solutes in the descending LOH
D. Increasing water permeability of the collecting duct
E. Blocking urea secretion in the LOH
D. Increasing water permeability of the collecting duct
Secretion of ADH by the posterior pituitary is decreased by
A. An increase in BP in the renal artery B. Increased pressures in the cardiac atria C. A decrease in BP in the carotid sinus D. An increase in plasma osmolality E. Dehydration
B. Increased pressures in the cardiac atria
Which statement is true about the renal cortex?
A. Contains 60% of the glomeruli
B. There is a gradient of osmolality that increases from the capsule toward the corticomedullary junction
C. The cortical interstitium contains virtually the same concentration of small solutes as does the peritubular capillary blood
D. There are no tubular segments in the cortex beyond the proximal convoluted tubule
E. The thick ascending limb of the LOH begins at the corticomedullary junction
C. The cortical intertitium contains virtually the same concentration of small solutes as does the peritubular capillary blood