Regulation of duodenal bicarbonate secretion during stress by corticotropin-releasing factor and beta-endorphin.
AUTOR(ES)
Lenz, H J
RESUMO
Proximal duodenal mucosal bicarbonate secretion is an important factor in the pathogenesis of duodenal ulcer disease. To examine the central nervous system regulation of duodenal bicarbonate secretion, an animal model was developed that allowed cerebroventricular and intravenous injections as well as collection of duodenal perfusates in awake, freely moving rats. The hypothalamic peptide corticotropin-releasing factor (CRF) and stress (physical restraint) significantly stimulated duodenal bicarbonate secretion. These responses were abolished by pretreatment of the animals with the CRF receptor antagonist alpha-helical CRF-(9-41), hypophysectomy, and naloxone. In contrast, blockade of autonomic efferents by surgical and pharmacological means did not prevent the stimulatory effects of stress and CRF. Intravenous, but not cerebroventricular, administration of beta-endorphin that produced plasma concentrations of beta-endorphin that were similar to those produced by exogenous CRF and stress significantly stimulated duodenal bicarbonate secretion. These results indicate that endogenous CRF released during stress and exogenously administered CRF stimulate duodenal bicarbonate secretion by release of beta-endorphin from the pituitary, thus, demonstrating a functional hypothalamus-pituitary-gut axis.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=286703Documentos Relacionados
- Noradrenergic inhibition of canine gallbladder contraction and murine pancreatic secretion during stress by corticotropin-releasing factor.
- Involvement of corticotropin-releasing factor in chronic stress regulation of the brain noradrenergic system.
- Corticotropin-releasing factor stimulates phospholipid methylation and corticotropin secretion in mouse pituitary tumor cells.
- Social stress-induced bladder dysfunction: potential role of corticotropin-releasing factor
- Characterization of rat hypothalamic corticotropin-releasing factor.