The Pituitary Gland

The pituitary gland is a small endocrine organ located in the sphenoid bone under the hypothalamus.

Primarily, the pituitary in adults has two distinct anatomical and functional regions— the anterior and posterior lobes.

The two parts of the anterior lobe— pars distalis and pars tuberalis, comprise glandular epithelial tissue, which produces various hormones.

The anterior lobe has a vascular connection with the hypothalamus via the hypophyseal portal system.

The hypothalamic hormones secreted by cells of the ventral hypothalamus travel through this portal system and control the hormone secretion by cells of the anterior lobe.

The posterior pituitary lobe also has two parts, infundibulum—a funnel-shaped stalk and pars nervosa.

The infundibulum allows the passage of the supra-optic and paraventricular nuclei axons of the hypothalamic-hypophyseal tract, maintaining a neural connection with the hypothalamus.

This tract delivers the ready-made hormones secreted by these hypothalamic neurosecretory cells into the posterior pituitary lobe, where they are stored until release.