Which of the following occurs after stimulation of the macula densa cells
A)vasodilation of the afferent arteriole
B)secretion of erythropoietin
C)increased GFR
D)vasoconstriction of the afferent arteriole

Question

Quizplus · Accepted Answer

Stimulation of the macula densa cells causes a feedback mechanism to increase filtration resistance, causing vasoconstriction of the afferent arteriole to decrease glomerular filtration rate (GFR). Therefore, option D is the correct choice. Afferent arteriole vasoconstriction reduces the flow of blood into the glomerulus, reducing the filtration rate. Vasodilation would have the opposite effect. Secretion of erythropoietin occurs in the interstitial cells of the kidney (peritubular cells), which produces red blood cells in response to low oxygen levels in the blood. Increased GFR is not associated with the stimulation of the macula densa cells; it is regulated by other mechanisms like renal autoregulation and hormonal regulation.

Which of the Following Occurs After Stimulation of the Macula