pituitary –anterior pituitary produces several hormones: 1. HGH (human growth hormone) – controls growth; also known as somatotropin (non-steroid) –-spurs body growth by increasing the absorption of calcium in the digestive system, increasing the rate of cell division/growth, and increasing protein & fat metabolism. –-HGH levels decline rapidly after adolescence prolactin – stimulates mammary gland tissue and milk production (non-steroid) –- increased prolactin levels during pregnancy suppress the production of LH which stops ovulation.

Anterior pituitary –3. TSH (thyroid stimulating hormone) – controls secretion of thyroxine in the thyroid gland –4. adrenocorticotrophin (ACTH) – regulates production of cortisol and aldosterone in the adrenal cortex –5. FSH (follicle stimulating hormone) – stimulates development of gametes (sperm and egg) –6. LH (lutenizing hormone) – in females, stimulates ovulation; in males, helps stimulates testosterone production

Posterior pituitary gland stores and releases ADH and oxytocin made by the hypothalamus –Oxytocin stimulates contraction of the smooth muscles in the uterus during childbirth. Towards the end of the pregnancy, the baby’s head pushes against the opening of the uterus. Pressure receptors in the uterus send impulses to the hypothalamus. This triggers the release of oxytocin from the posterior pituitary. The presence of oxytocin stimulates the uterine muscles to contract. Each contraction causes additional impulses from the pressure receptors and the release of even more oxytocin. This process ends with the birth of the baby (positive feedback loop).

Posterior pituitary gland –Vasopressin - also called antidiuretic hormone (ADH) produced by the hypothalamus and released through the pituitary gland -Special cells in the hypothalamus called osmoreceptors, monitor sodium levels in the blood. High sodium levels trigger the release of ADH which increases the reabsorption of water. -The pituitary also secretes ADH in response to a sudden drop in blood pressure (i.e. cuts). ADH causes a constriction (narrowing) of the damaged arteries reducing the amount of blood loss.

Hypothalamus It produces 2 hormones (both stored and secreted from the posterior pituitary gland) –1. ADH (anti-diuretic hormone): controls water levels –2. oxytocin: triggers muscle contractions in childbirth and promotes lactation interacts constantly with the pituitary gland