ATI Pathophysiology Practice Exam

Antidiuretic hormone (ADH), also known as vasopressin, is the hormone that primarily regulates urine output. It is produced in the hypothalamus and released from the posterior pituitary gland. ADH plays a critical role in maintaining the body's water balance by promoting the reabsorption of water in the kidneys. When the body requires more water conservation, such as in times of dehydration or high plasma osmolarity, ADH levels increase, leading to more water being reabsorbed back into the bloodstream and resulting in less dilute urine.

In contrast, while aldosterone is important in regulating sodium and potassium levels, and thus indirectly influencing water retention, its primary role is not directly related to urine output. Cortisol, a glucocorticoid hormone, influences various metabolic processes but does not play a direct role in the regulation of urine volume. Insulin is crucial in glucose metabolism and does not have a direct role in urine output regulation either. Therefore, among the options provided, antidiuretic hormone is the one specifically responsible for regulating urine output through its actions on the kidneys.