What is the basic sequence of the hypothalamic-pituitary-adrenal axis leading to cortisol release?

What is the basic sequence of the hypothalamic-pituitary-adrenal axis leading to cortisol release?

• A. Hypothalamus releases CRH → pituitary releases ACTH → adrenal cortex releases cortisol
• B. Hypothalamus releases ACTH → pituitary releases CRH → adrenal cortex releases cortisol
• C. Adrenal cortex releases CRH → hypothalamus releases ACTH → pituitary releases cortisol
• D. Pituitary releases cortisol → hypothalamus releases CRH → adrenal cortex releases ACTH

Answer: (A)

The sequence starts with the hypothalamus releasing CRH, which then stimulates the pituitary to release ACTH. ACTH travels to the adrenal cortex, prompting it to produce and release cortisol. This order—CRH from the hypothalamus, ACTH from the pituitary, cortisol from the adrenal cortex—is the correct flow. Cortisol then feeds back to dampen CRH and ACTH production to help terminate the response.

The sequence starts with the hypothalamus releasing CRH, which then stimulates the pituitary to release ACTH. ACTH travels to the adrenal cortex, prompting it to produce and release cortisol. This order—CRH from the hypothalamus, ACTH from the pituitary, cortisol from the adrenal cortex—is the correct flow. Cortisol then feeds back to dampen CRH and ACTH production to help terminate the response.