Peripherally administered CRF stimulates colonic motility via central CRF receptors and vagal pathways in conscious rats. Am J Physiol Regul Integr Comp Physiol 2006 Jun;290(6):R1537-41
Date
11/15/2005Pubmed ID
16284082DOI
10.1152/ajpregu.00713.2005Scopus ID
2-s2.0-33744813779 (requires institutional sign-in at Scopus site) 37 CitationsAbstract
Corticotropin releasing factor (CRF) is one of the most important factors in the mechanism of stress-induced stimulation of colonic motility. However, it is controversial whether stress-induced stimulation of colonic motility is mediated via central or peripheral CRF receptors. We investigated the hypothesis that peripherally injected CRF accelerates colonic motility through the central CRF receptor, but not the peripheral CRF receptor. A strain gauge transducer was sutured on the serosal surface of the proximal colon. Colonic motility was monitored before and after the peripheral injection of CRF. An in vitro muscle strip study was also performed to investigate the peripheral effects of CRF. Subcutaneous injection of CRF (30-100 microg/kg) stimulated colonic motility in a dose-dependent manner. The stimulatory effect of peripherally administered CRF on colonic motility was abolished by truncal vagotomy, hexamethonium, atropine, and intracisternal injection of astressin (a CRF receptor antagonist). No responses to CRF (10(-9) -10(-7) M) of the muscle strips of the proximal colon were observed. These results suggest that the stimulatory effect of colonic motility in response to peripheral administration of CRF is mediated by the vagus nerve, nicotinic receptors, muscarinic receptors, and CRF receptors of the brain stem. It is concluded that peripherally administered CRF reaches the area postrema and activates the dorsal nucleus of vagi via central CRF receptors, resulting in stimulation of the vagal efferent and cholinergic transmission of the proximal colon.
Author List
Tsukamoto K, Nakade Y, Mantyh C, Ludwig K, Pappas TN, Takahashi TAuthor
Kirk A. Ludwig MD Chief, Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Afferent PathwaysAnimals
Atropine
Carbachol
Colon
Consciousness
Corticotropin-Releasing Hormone
Electric Stimulation
Gastrointestinal Motility
Hexamethonium
Male
Muscle Contraction
Muscle, Smooth
Neuroprotective Agents
Peptide Fragments
Rats
Rats, Sprague-Dawley
Receptors, Corticotropin-Releasing Hormone
Stress, Physiological
Vagotomy, Truncal
Vagus Nerve