Antidiuretic Hormone (ADH)

Antidiuretic hormone (ADH), also known as vasopressin, is a hormone produced by the hypothalamus and released by the posterior pituitary gland. It plays a crucial role in the regulation of water balance in the body.

Function of Antidiuretic Hormone

ADH acts on the kidneys to increase water reabsorption, which helps to concentrate the urine and reduce the amount of water excreted from the body. This mechanism helps to maintain the body's water balance and prevent dehydration.

Regulation of ADH Release

The release of ADH is tightly regulated by the body's internal environment. Factors such as blood osmolarity, blood volume, and blood pressure can stimulate or inhibit the release of ADH. For example, an increase in blood osmolarity (concentration of solutes in the blood) or a decrease in blood volume can trigger the release of ADH to conserve water and prevent dehydration.

Disorders Related to ADH

Imbalances in ADH production or function can lead to medical conditions such as diabetes insipidus (characterized by excessive urination and thirst) or syndrome of inappropriate antidiuretic hormone (SIADH), where the body retains water excessively, leading to low sodium levels in the blood.

Study Guide for Antidiuretic Hormone

1. Describe the role of ADH in the regulation of water balance in the body.
2. Explain how ADH acts on the kidneys to reduce water excretion.
3. Discuss the factors that regulate the release of ADH in the body.
4. Identify and explain the medical conditions associated with ADH imbalances.