Final answer:
ADH, or vasopressin, regulates water reabsorption in the kidneys, increasing the permeability of the collecting ducts to allow more water back into the bloodstream, thus reducing urine volume and maintaining the body's fluid balance.
Step-by-step explanation:
The effect of antidiuretic hormone (ADH) on kidney function is significant. ADH, produced in the hypothalamus and released from the posterior pituitary gland, regulates the amount of water excreted by the kidneys. This hormone, also known as vasopressin, increases the permeability of the collecting ducts in the kidneys by inserting water channels called aquaporins. This action allows for greater water reabsorption from the urine into the blood, reducing urine volume and correcting blood osmolarity. ADH release is triggered by an increase in blood osmolarity, such as during dehydration. When osmolarity is restored, ADH secretion diminishes.
Substances like alcohol can reduce ADH secretion, leading to less water reabsorption in the kidneys, increased urine production, and potential dehydration. In summary, ADH plays a crucial role in osmoregulation, helping to conserve water in the body and regulate blood pressure.