This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Renal physiology, Subject name: Physiology
Relaxation of mesangial cells is responsible for 
Select and explain. 
A. Absorption of glucose, B. Maintenance of blood flow, C. Osmotic gradient in medulla, D. Secretion of uric acid
B: Maintenance of blood flow
Answer: B: Maintenance of blood flow 
Explanation: Mesangial cells are specialized cells around blood vessels in the kidneys, at the mesangium. They are specialized smooth muscle cells that function to regulate blood flow through the capillaries,Ref: Ganong&;s review of medical physiology; 24th edition; page no: 673