Central regulation of micturition in the rat by corticotropin-releasing hormone from Barrington's nucleus

Abstract

Barrington's nucleus, a pontine nucleus implicated in micturition, contains numerous corticotropin-releasing hormone (CRH) neurons that project to the spinal parasympathetic nucleus that innervates the bladder. We now report that CRH from Barrington's nucleus may serve to inhibit micturition. Selective chemical activation of Barrington's nucleus by microinjection of glutamate evoked bladder contractions that were increased in magnitude after intrathecal administration of a CRH antagonist, D-PheCRH 12–41. In contrast, intrathecally administered CRH decreased the magnitude of Barrington's stimulated bladder contractions. These results suggest that activation of Barrington's nucleus releases an excitatory neurotransmitter responsible for bladder contractions, and CRH, which inhibits this neurotransmitter. The balance between these two neuromediators may regulate bladder contractility, and thereby, urinary continence.