The hypothalamus is the major integrating link between the nervous and endocrine systems. It is located anterior to the brainstem at the base of the frontal lobe of the brain. The hypothalamus has three separate pathways for secretion of hormones:
- The hypophyseal portal system carries releasing hormones in the blood from the hypothalamus to the anterior pituitary to control secretion of hormones that act on other endocrine glands (tropic hormones).
- Sympathetic axons travel to the adrenal medulla where neuroendocrine cells secrete mostly epinephrine.
- Oxytocin and ADH are secreted from neuroendocrine cells that arise in the hypothalamus and travel into the posterior pituitary gland. Oxytocin is important for milk ejection and childbirth. ADH (anti-diuretic hormone) preserves body water by preventing diuresis (dilute urine).
Making a Difference in the World 