2B), the absolute nadirs in IGP were similar at each dose tested (Fig

2B), the absolute nadirs in IGP were similar at each dose tested (Fig. the bulk response. Unexpectedly, efferent excitation in the pVGV was significantly shorter lived and had a significantly shorter decay half-time than did efferent inhibition in the dVGV, indicating that distinct pathways drive CCK-evoked outflow to the proximalvs.the distal stomach. Efferent inhibition in the dVGV began several seconds before, and persisted significantly longer than, simultaneously recorded dVGV afferent excitation. Thus, dVGV afferent excitation could not account for the pattern of dVGV efferent inhibition. However, the time course of dVGV afferent excitation paralleled that of pVGV efferent excitation. Similarly, the duration of CCK-8-evoked afferent responses recorded in the Verucerfont accessory celiac branch of the vagus (ACV) matched the duration of dVGV efferent responses. The observed temporal relationships suggest that postprandial effects on gastric complicance of CCK released from intestinal endocrine cells may require circulating concentrations to rise to levels capable of exciting distal gastric afferent fibres, in contrast to more immediate effects on distal gastric contractile activity mediated via vago-vagal reflexes initiated by paracrine excitation of Verucerfont intestinal afferents. == Non-technical summary Verucerfont == Gut activity is controlled by the vagus nerves. In anaesthetized rats, both sensory and motor nerve activity evoked by intravenous injection of the gut hormone cholecystokinin were recorded in separate sub-branches of the gastric Verucerfont vagus nerve that supply the forestomach and hindstomach, respectively. Activity in the forestomach branch has not been studied before. Motor nerve activity in response to cholecystokinin differed between the two branches, in both timing and direction. Motor output to the forestomach paralleled sensory input from the hindstomach, while motor output to the hindstomach paralleled sensory input from the intestines. The data suggest that cholecystokinin released in the intestines after a meal immediately influences churning and propulsion of food by the hindstomach, via reflexes initiated by nearby intestinal sensory nerve terminals, but may influence gastric capacity only later, once circulating levels of cholecystokinin rise to levels capable of activating sensors in the hindstomach. == Introduction == The mechanical repertoire of the stomach can be divided broadly into a reservoir function responsible for adjusting stomach capacity and tone, and a pumping function responsible for mixing ingesta and gastric secretions, trituration and propulsion of the resulting chyme. These functions are regionally segregated to the proximal and distal stomach, respectively. While anatomically distinct, the activities of these Bmp15 two regions of the stomach are typically regulated coordinately. Stimuli that delay gastric emptying often cause both a reduction in phasic contractile activity of the hindstomach and relaxation of the forestomach, while stimuli or conditions that increase gastric emptying generally have the opposite effects (Azpiroz & Malagelada, 1986;van der Schaaret al.2001;Tacket al.2006). Central control of gastric contractile activity and of accommodation during normal digestion is mediated primarily via efferent pathways in the subdiaphragmatic vagi, and both functions are subject to modulation by vago-vagal reflexes, i.e. changes in vagal afferent input from the gut which in turn alter efferent output to the gut (Harperet al.1959;Azpiroz & Malagelada, 1986). It has been known for over a century that a major vagal pathway controlling gastric accommodation is inhibitory, i.e. that excitation of Verucerfont the relevant preganglionic fibres reduces forestomach tone, while the predominant vagal pathway controlling the gastric pump is excitatory (Langley, 1898;McSwiney, 1931). However, all regions of the stomach appear to receive a combination of excitatory and inhibitory vagal efferent inputs, whose relative roles in controlling motor functions of the stomach are an area of ongoing research interest (Zhenget al.1999;Guoet al.2001;Hermannet al.2006;Pearsonet al.2007;Hermanet al.2008). The clinical importance of the vagal regulation of gastric compliance is emphasized by recent findings linking impaired accommodation to functional dyspepsia (Tacket al.1998,2001). The predominant vagal input to the stomach arrives via the gastric vagi (Berthoudet.