Contrasting effects of ghrelin and des-acyl ghrelin on the lumbo-sacral defecation center and regulation of colorectal motility in rats.

摘要: Background  We have previously demonstrated that a centrally penetrant ghrelin receptor agonist enhances colorectal motility, through activation of the lumbo-sacral defecation center (L6-S1 region spinal cord) in rats. In present study, we examined effects native peptide and its non-acylated counterpart eliciting this stimulatory effect on motility. Methods  Rats were anesthetised with α-chloralose ketamine, intraluminal pressure propelled liquid volume recorded vivo. Key Results  Intrathecal application acylated to L6-S1 cord, but not intravenous application, elicited groups phasic increases associated increased fluid output anal cannula. The was dose-dependent. colokinetic prevented if pelvic nerves severed. Reverse transcription polymerase chain reaction revealed expression genes cord. contrast ghrelin, des-acyl failed cause changes motility. However, when applied simultaneously at region, ghrelin-induced enhancement motility significantly attenuated. Conclusion & Inferences  It is concluded acylation essential promote propulsive contractions colorectum opposes effect. At most other sites action, either has no or it mimics ghrelin. This first evidence action