PATHOLOGY

PATHOLOGY MCQ

URINARY SYSTEM

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
When an increase in blood pressure stretches arterioles in the kidneys, this describes the fact that they vasoconstrict to reduce flow without feedback from the rest of the body.
A
autoregulation
B
homeostasis
C
auto centering
D
vasodilation
Explanation: 

Detailed explanation-1: -The myogenic response is the reflex response of the afferent arterioles to changes in blood pressure. Increased blood pressure increases the tension in the vascular wall, and the vascular smooth muscle contracts. Similarly, decreased blood pressure decreases the tension and the smooth muscle relaxes.

Detailed explanation-2: -Because renal blood flow and GFR normally change in parallel, any increase in renal blood flow causes an increase in GFR. The increased renal O2 consumption (GFR) is offset by an increase in renal oxygen delivery (renal blood flow). This results in a constant arteriovenous O2 difference across the kidney.

Detailed explanation-3: -Constriction of the afferent arterioles has two effects: it increases the vascular resistance which reduces renal blood flow (RBF), and it decreases the pressure downstream from the constriction, which reduces the GFR.

There is 1 question to complete.