Urinalysis and Body Fluids 6th Edition by Majorie DiLorenzo, Susan Strasinger

Exercise 53

To provide an accurate measure of renal blood flow, a test substance should be completely:

A. Filtered by the glomerulus

B. Reabsorbed by the tubules

C. Secreted when it reaches the distal convoluted tubule

D. Cleared on each contact with functional renal tissue

Step 1 of 2

Renal blood flow:

• Renal blood flow is the volume of blood moving into the kidney per unit of time.

PAH ( p -aminohippuric) test:

p-aminohippuric test is helpful in testing of renal blood flow and tubular secretion.

• The substance used in this test, should get cleared from the blood when it appears in kidney.

• PAH is loosely attached to the blood plasma that can be easily cleared from blood when leaving peritubular capillaries.

• Proximal convoluted tubule secretes the PAH

Therefore, the substances “contacted with the functional renal tissue”, cleared from the blood will provide the accurate result of renal blood flow. Hence, the correct answer is option.