Hypothalamus & Pituitary Gland

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The hypothalamus is a small region of the brain. It's located at the base of the brain, near the pituitary gland. While it's very small, the hypothalamus plays a crucial role in many important functions, including: releasing hormones.
The pituitary gland , also called the hypophysis, is a small gland and is connected to the hypothalamus by the pituitary stalk. Physiologically, the pituitary gland is divisible into two distinct portions: the anterior pituitary, also known as the adenohypophysis, and the posterior pituitary, also known as the neurohypophysis.
Six important peptide hormones are secreted by the anterior pituitary.
These hormones include ;
Growth hormone which promotes growth of the entire body. Adrenocorticotropin which controls the secretion of some of the adrenocortical hormones.
Thyroid stimulating hormone which controls the rate of secretion of T3 and T4 by the thyroid gland.
And prolactin which promotes mammary gland development and milk production.
And two important peptide hormones are secreted by the posterior pituitary.
Antidiuretic hormone which controls the rate of water excretion into the urine and Oxytocin which helps express milk from the glands of the breast to the nipples during suckling.
The hypothalamus and pituitary gland function in a coordinated fashion to orchestrate many of the endocrine systems.
The connections between the hypothalamus and the posterior
lobe of the pituitary are neural. In fact, the posterior pituitary is a collection of nerve axons whose cell bodies are located in the hypothalamus. Thus, the hormones secreted by the posterior lobe (ADH and oxytocin) are actually neuropeptides; in other words, they are peptides released from neurons.
Secretion by the anterior pituitary is controlled by hormones called hypothalamic releasing and hypothalamic inhibitory hormones secreted within the hypothalamus and then conducted to the anterior pituitary through minute blood vessels called hypothalamic hypophysial portal vessels. In the anterior pituitary, these releasing and inhibitory hormones act on the glandular cells to control their secretion.