What does the hypothalamus produce to control the anterior pituitary?

• A. Releasing Hormones
• B. Inhibitory Hormones
• C. Posterior Pituitary Hormones
• D. Regulatory Hormones

Answer: (D)

Hypothalamic control of the anterior pituitary occurs through regulatory hormones that the hypothalamus produces and releases into the hypophyseal portal system. These hormones include releasing hormones that stimulate, and inhibitory hormones that suppress, the secretion of anterior pituitary hormones. This single set of regulatory signals governs the release of hormones like ACTH, TSH, GH, FSH/LH, and prolactin from the anterior pituitary. In contrast, hormones from the posterior pituitary (such as oxytocin and vasopressin) are produced in the hypothalamus but released from the posterior lobe and do not regulate the anterior pituitary. So regulatory hormones best describe the hypothalamus’s role in directing anterior pituitary activity.