What hormone is secreted by the pituitary to stimulate the adrenal cortex?

The hormone that stimulates the adrenal cortex is Adrenocorticotropic Hormone (ACTH). This hormone is produced and secreted by the anterior pituitary gland and plays a vital role in the body's stress response. When ACTH is released into the bloodstream, it targets the adrenal cortex, which is the outer layer of the adrenal glands.

Once stimulated by ACTH, the adrenal cortex produces and releases glucocorticoids, such as cortisol, which help regulate metabolism, immune response, and stress management. This process is part of the hypothalamic-pituitary-adrenal (HPA) axis, a crucial system for maintaining homeostasis.

The other hormones listed do not have this specific function. Thyroid Stimulating Hormone, for example, primarily acts on the thyroid gland to regulate metabolism. Prolactin is involved in milk production and reproduction, while insulin, produced by the pancreas, regulates blood glucose levels. Thus, ACTH’s role in stimulating the adrenal cortex is distinct and essential for the physiological response to stressors.