Hypothalmic pituitary axis physiology|hypothalamic hypophyseal portal system 

Hypothalamic- pituitary axis -physiology|hypothalamic hypothalamic hypophyseal -portal system|hypothalamic hypophyseal tract |hypothalamic nuclei and their functions|hypothalamic and pituitary hormones|
Hypothalamic nuclei
Peptides released near the median eminence from hypothalamic nuclei are transported to the anterior pituitary, where they apply their effects. Branches from the internal carotid artery provide the blood supply to the pituitary. The superior hypophyseal arteries form the primary capillary plexus that supplies blood to the median eminence. From this capillary system, the blood is drained in hypophyseal portal veins into the secondary plexus. The peptides released at the median eminence enter the primary plexus capillaries. From there, they are transported to the anterior pituitary via hypophyseal portal veins to the secondary plexus. The secondary plexus is a network of fenestrated sinusoid capillaries that provide blood to the anterior pituitary. The cells of the anterior pituitary express specific G protein-coupled receptors that bind to the neuropeptides, activating intracellular second messenger cascades that produce the release of anterior pituitary hormones.
The following is a list of hormones that rely on the hypophyseal portal system to indirectly mediate their function by acting as a means of transportation from various nuclei of the hypothalamus to the anterior pituitary.
Gonadotropin-releasing hormone (GnRH): regulates the release of follicle stimulating hormone and luteinizing hormone from the anterior pituitary; this pathway plays a critical role in reproductive activity and development
Corticotropin-releasing hormone (CRH): regulates the release of adrenocorticotropic hormone from the anterior pituitary; this cascade is primarily responsible for stress responses
Growth hormone-releasing hormone (GHRH): regulates the release of growth hormone from the anterior pituitary; as the name suggests, its main function is to help control cell growth, metabolism, and reproduction
Thyrotropin-releasing hormone (TRH): regulates the release of thyroid-stimulating hormone from the anterior pituitary; functions to mediate various responses in the thyroid gland, including additional hormone synthesis
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