The. Hydrobromide Arecoline (Ah) To Promote The Study Of The Effects Of Gastrointestinal Motility And Proteomics Preliminary

Objective:1. To observe the effect of arecoline hydrobromide (Ah) on the differentsegments isolated gastric smooth muscle strips and to examine thepossible mechanism of its action.2. It is well known that the Ah can promote contraction of rat's smoothmuscle, however the mechanisms is far from clear. To explore into themechanisms, proteomic approach was used to compare the proteinexpression profiles between rat smooth muscle cell (SMC) with andwithout stimulation to Ah.Methods:1. Gastric smooth muscle strips from guinea pig (six different parts) weresuspended in issue chambers containing 4 ml Krebs solution at 37℃andits spontaneous contractiveactivity was observed and recorded. Theresponse to arecoline and the effect of atropine and verapamil onarecoline-induced contraction were also assessed.2. In Ah-treated groups, SMC were cultured in Ah-containing (1×10^-5 mol/L) medium; in control groups, SMC were cultured in vehiclemedium at the same condition, the cells were collected at the 15 minlater, and the collagenase- digested cells were resolved in cell lysisbuffer, the proteins were seperated in two-dimensional gelelectrophoresis(2-DE). The differential protein expressions between thetwo groups of cell were analyzed using image analysis software.Results:1. (1) Arecoline significantly raised the tension of all gastric muscle stripsin Guinea pig and also increased contractile amplitude and areas undercurves of all gastric mucle strips and the results shows there is adifference among different parts, longitudinal muscle strips (LMS)followed the order: the contractile amplitude of antral LMS larger thanLMS of gastric fundus and LMS of gastric body significantly (P＜0.05);the areas under curves of antral LMS larger than LMS of gastric bodysignificantly (P＜0.05). The ring muscle strips (RMS) followed the order:the the contractile amplitude of antral RMS larger than RMS of gastricfundus significantly (P＜0.05); the areas under curves of antral RMSlarger than RMS of gastric body significantly and the RMS of gastricfundus (P＜0.05), and the areas under curves of RMS of gastric bodylarger than RMS of gastric fundus significantly (P＜0.05). (2) The effectof arecoline to gastric contraction could be eliminated by atropine and verapamil partially and increased mean contractile amplitude (P＜0.01).2. The reproducible 2-DE images were successfully obtained. There were7 proteins down-regulated in the Ah-treated cells harvested at 15 min(Ahl 5 min) compared to the control group (Ctr15 min);Conclusion:1. The result indicates that arecoline significantly had excited action oncontractile activity of isolated gastric muscle strips in guinea pig andthe excited action of arecoline to stomach may be via M-muscariniccholinergic receptor and L-type calcium channel.2. It suggested that SMC treated with Ah could induce the changes ofprotein spectrum, and the results may provide insight into themechanism of the anabolic effect of Ah. and the conclusion may laysthe foundation of deep research in promoting colonic smooth musclemotility of Ah.