Development and Subdivision of the Hypophysis

Development and Subdivision of the Hypophysis

The hypophysis, or pituitary gland, consists of two parts, namely, the adeno-hypophysis (anterior lobe) (AB1), whichdevelops from an evagination of the roof of the primitive foregut (Rathke’s pouch), and the neurohypophysis (posterior lobe) (AB2), which represents an evagination of the floor of the diencephalon. The adenohy-pophysis is an endocrine gland, while the neurohypophysis is a part of the brain com-posed of nerve fibers, a capillary bed, and a unique type of glia, the pituicytes. The two parts of the hypophysis adjoin each other, bringing the nervous system into close asso-ciation with the endocrine system.