Stimulation of the macula densa cells
A) results in vasodilation of the afferent arteriole
B) results in vasoconstriction of the afferent arteriole
C) increases GFR
D) results in vasodilation of the afferent arteriole and results in vasoconstriction of the afferent arteriole
E) results in vasodilation of the afferent arteriole and increases GFR

Question

Quizplus · Accepted Answer

Stimulation of the macula densa cells results in the release of ATP, which leads to the constriction of the afferent arteriole, reducing blood flow to the glomerulus and decreasing GFR. This is known as the tubuloglomerular feedback mechanism, which helps regulate GFR and maintain the balance of solutes and water in the body. Vasodilation of the afferent arteriole would increase blood flow to the glomerulus and increase GFR, which is opposite of what occurs with macula densa stimulation.

Stimulation of the Macula Densa Cells