Through that stalk, the hypothalamus communicates with the anterior lobe via hormones and the posterior through nerve impulses. The hypothalamus, which is above your pituitary gland, is the control center of some of your body’s basic operations.

The hypothalamus–pituitary complex is located in the diencephalon of the brain. The hypothalamus and the pituitary gland are connected by a structure called the infundibulum, which contains vasculature and nerve axons.

In addition to glucocorticoid feedback, the HPA axis is regulated at the level of the hypothalamus by a diverse group of afferent projections from limbic, mid-brain, and brain stem nuclei.

During stress, the hypothalamic-pituitary-adrenal (HPA) axis is activated. Hypothalamic neurons within the HPA axis secrete corticotropin-releasing hormone that causes the release of adrenocorticotrophic hormone (ACTH) from the pituitary. The ACTH causes the adrenal gland to secrete cortisol (a stress hormone).

The pituitary gland has two main parts, the anterior pituitary gland and the posterior pituitary gland. The gland is attached to a part of the brain (the hypothalamus) that controls its activity.

The hypothalamic-pituitary-adrenal axis, or HPA axis as it is commonly called, describes the interaction between the hypothalamus, pituitary gland, and adrenal glands. The hypothalamus and pituitary gland are located just above the brainstem, while the adrenal glands are found on top of the kidneys.

The hypothalamus works with the pituitary gland, which makes and sends other important hormones around the body. Together, the hypothalamus and pituitary gland control many of the glands that produce hormones of the body, called the endocrine system. This includes the adrenal cortex, gonads, and thyroid.

Specifically, the hypothalamic-pituitary axis directly affects the functions of the thyroid gland, the adrenal gland, and the gonads, as well as influencing growth, milk production, and water balance (table 1) [1-4].

The pituitary gland has two main parts, the anterior pituitary gland and the posterior pituitary gland. The gland is attached to a part of the brain (the hypothalamus) that controls its activity. The anterior pituitary gland is connected to the brain by short blood vessels.

It connects to the pituitary gland by the stalk-like infundibulum. The pituitary gland consists of an anterior and posterior lobe, with each lobe secreting different hormones in response to signals from the hypothalamus. The posterior pituitary is actually an extension of the neurons of the paraventricular and supraoptic nuclei of the hypothalamus.

5. FUNCTION• The most important functions of the hypothalamus is to link the nervous system to the endocrine system via the pituitary gland.• It synthesizes and secretes certain neurohormones, often called hypothalamic-releasing hormones, and these in turn stimulate or inhibit the secretion of pituitary hormones.

Recall that the posterior pituitary does not synthesize hormones, but merely stores them. In contrast, the anterior pituitary does manufacture hormones. Like the posterior pituitary the release of hormones from the anterior pituitary is controlled by the hypothalamus.

The adenohypophysismakes up the anterior portion of the pituitary and is often referred to as the anterior lobe of the pituitary, and its hormones are referred to as anterior pituitary hormones.