The Role of Brain Peptides in the Control of Anterior Pituitary Hormone Secretion

Abstract

A host of peptides act within the hypothalamus and also directly on the pituitary to control the secretion of anterior pituitary hormones. The classical releasing and inhibiting hormones act directly on the pituitary to inhibit or stimulate the release of anterior pituitary hormones. They appear also to act within the brain to modulate their own release and that of other releasing factors. With the discovery of many additional brain peptides, most of which were found initially in the gastrointestinal tract, many of these have also been examined, and it is apparent that there are important hypothalamic actions of a number of these peptides to alter pituitary hormone secretion (McCann et al., 1984b). In this chapter, we review some of our recent work in this area beginning with an examination of possible additional peptidic releasing or inhibiting factors that may directly alter pituitary hormone secretion and continuing with an examination of the intrahypothalamic action of the various peptides to alter their own release and that of pituitary hormones.