VIP occurs in intrathyroidal nerves and stimulates thyroid hormone secretion

Abstract

Vasoactive intestinal polypeptide (VIP) has powerful effects on the secretion from several endocrine and exocrine glands and occurs in nerves with a ubiquitous distribution in the body. Neuronal VIP may be a regulator of such secretion and may be involved in the regulation of exocrine pancreatic function. Adrenergic and cholinergic nerves participate in the regulation of thyroid hormone secretion. Combined immunohistochemical and immunochemical studies are described which show that the thyroid of several species [cat, pig, man, mouse, rat and guinea pig] is supplied with VIP-containing nerve fibers that surround blood vessels and run between and along thyroid follicles and that in the mouse neuronal VIP participates in the regulation of thyroid hormone secretion through a mechanism that is mediated by cAMP.