What is the role of Adrenocorticotropic hormone (ACTH)?

Adrenocorticotropic hormone (ACTH) primarily regulates the secretion of glucocorticoids from the adrenal cortex. It is synthesized in the pituitary gland in response to corticotropin-releasing hormone (CRH) from the hypothalamus. The release of ACTH into the bloodstream acts on the adrenal cortex, prompting it to produce and release glucocorticoids, such as cortisol. These hormones play critical roles in metabolism, immune response modulation, and stress management.

The other options describe hormones or processes that are not influenced by ACTH. For instance, the stimulation of thyroid hormone release is governed by thyroid-stimulating hormone (TSH), while red blood cell production is primarily regulated by erythropoietin. Calcium levels in the blood are closely managed by parathyroid hormone and calcitonin, rather than ACTH. Therefore, the correct understanding of ACTH's function is essential in grasping the hormonal interactions within the endocrine system.