In diabetes mellitus, why does polyuria occur?
A) Hypoglycemia causes the excretion of a dilute urine.
B) Hyperglycemia causes increased permeability of the renal tubules to water.
C) A lack of ADH decreases water reabsorption.
D) A lack of insulin decreases water reabsorption.
E) Hyperglycemia causes some glucose to remain in the renal tubules which pulls water with it by osmosis.

Question

Quizplus · Accepted Answer

Hyperglycemia leads to an increased concentration of glucose in the renal tubules. When the glucose concentration exceeds the renal threshold, not all glucose can be reabsorbed, and it remains in the tubules. This unabsorbed glucose exerts an osmotic force, pulling water into the tubules and preventing its reabsorption, which results in an increased volume of urine, a condition known as polyuria.

In Diabetes Mellitus, Why Does Polyuria Occur