Which component of the nephron is the receptor site for antidiuretic hormone?

The collecting ducts are indeed the receptor sites for antidiuretic hormone (ADH), also known as vasopressin. This hormone plays a crucial role in regulating water balance in the body by increasing the permeability of the collecting ducts to water. When ADH is present, the collecting ducts allow more water to be reabsorbed back into the bloodstream, which helps concentrate urine and reduce water loss.

By binding to specific receptors in the collecting ducts, ADH promotes the insertion of aquaporins, which are water channels that facilitate the passive movement of water across the cell membrane. This process is essential for maintaining fluid and electrolyte balance, especially during conditions of dehydration or when the body needs to conserve water.

Understanding the role of the collecting ducts in response to ADH is critical for comprehending how the kidneys function in fluid regulation and the implications of various disorders related to electrolyte imbalance and hydration status.