The hypothalamus regulates the pituitary gland and is therefore a central controller of many endocrine functions.
The hypothalamus is a small region near the base of the brain, below the thalamus and beside the third ventricle. It links the nervous system with the endocrine system by releasing regulatory hormones into blood vessels that lead to the anterior pituitary. These signals control pituitary release of hormones involved in growth, reproduction, stress, metabolism, and thyroid function.
The hypothalamus also produces oxytocin and vasopressin, which are transported to and released from the posterior pituitary. It helps regulate body temperature, hunger, thirst, sleep–wake rhythms, and autonomic activity. Its position allows it to integrate information about the body’s internal state with signals from the brain.
The phrase “master gland” more accurately describes the pituitary, but the hypothalamus directs much of the pituitary’s activity. The pineal gland is another endocrine structure in the brain, yet it mainly produces melatonin rather than controlling the pituitary.