Hormones produced by the posterior pituitary gland regulate water resorption and smooth muscle contraction. Which gland produces these hormones?

Hormones produced by the posterior pituitary gland regulate water resorption and smooth muscle contraction. Which gland produces these hormones?

• A. Anterior pituitary
• B. Posterior pituitary
• C. Thyroid
• D. Hypothalamus

Answer: (B)

Hormones that regulate water balance and smooth muscle contraction are produced by the hypothalamus and released by the posterior pituitary. The hypothalamus makes the hormones—vasopressin (antidiuretic hormone) and oxytocin—and these peptides are transported down nerve fibers to the posterior pituitary, where they are stored and released into the bloodstream as needed. Vasopressin acts on the kidneys to promote water reabsorption, helping control body water and urine concentration, and can influence vascular smooth muscle with vasoconstriction. Oxytocin drives smooth muscle contraction in the uterus during labor and also plays a role in milk ejection from the mammary glands. Because the production occurs in the hypothalamus, the gland that produces these hormones is the hypothalamus; the posterior pituitary is simply the storage and release site.

Hormones that regulate water balance and smooth muscle contraction are produced by the hypothalamus and released by the posterior pituitary. The hypothalamus makes the hormones—vasopressin (antidiuretic hormone) and oxytocin—and these peptides are transported down nerve fibers to the posterior pituitary, where they are stored and released into the bloodstream as needed. Vasopressin acts on the kidneys to promote water reabsorption, helping control body water and urine concentration, and can influence vascular smooth muscle with vasoconstriction. Oxytocin drives smooth muscle contraction in the uterus during labor and also plays a role in milk ejection from the mammary glands. Because the production occurs in the hypothalamus, the gland that produces these hormones is the hypothalamus; the posterior pituitary is simply the storage and release site.