| Objective: To investigate the effects and mechanism of capsaicin ongastric motility in water immersion restraint stress(WIRS) rats through testing therate of gastric emptying and the plasma motilin level, detecting the expression oftransient receptor potential type1, substance P and c-kit in gastric antrum, testingthe transcriptional level of c-kit mRNA and SCF mRNA in gastric antrum tissue.Methods:(1) The preparation of CAP feed: The95%CAP105.3mg (includingCAP100mg) was dissolved in edible oil(30ml).The mixture was blended withflour100g,then the CAP feed was prepared well.(2) The establishment of WIRSrat model:Twenty SD rats were randomly divided into control group and modelgroup. Rats in model group were proceed with water immersion restraint stressone hour a day for4consecutive weeks.Rats in control group were not imposedstress.(3)The experimental animal grouping of CAP intervention: Forty SD ratswere randomly divided into4groups:Group A(the normal control group), GroupB(the WIRS group), Group C(the WIRS+CAP group), Group D(the CAP group).(4) The specific method: Rats in Group A were freely accessed to food and waterfor4consecutive weeks. Rats in Group B were freely accessed to food and waterafter the stress for4consecutive weeks.Rats in Group C were fed the capsaicinfeed(capsaicin contet was1mg/g)5g/kg after the stress.After eating the capsaicinfeed,they were ate the normal feed for4weeks. Rats in Group D were fed thecapsaicin feed (capsaicin contet was1mg/d)5g/kg.After eating the capsaicin feed,they were ate the normal feed for4weeks. After4weeks, all the rats werefasted for24hours, and then lavaged them with phenol red solution(phenol redconcentration was50mg/dL) in the morning of the second day. All the rats werekilled30minutes later.(5)Detection index:①The gastric contents were collectedfor testing the gastric emptying rate of phenol red.②Collect2ml blood samplefrom the abdominal aorta,after centrifugation at4℃, the supernatant wasextracted and then the plasma MTL was detected by Elisa method.③Observe thegastric mucosa injury index and use the gastric mucosa for pathologicalexamination.④Use the gastric antrum tissue for testing the expression of TRPV1,SP and c-kit by immunohistochemical method.⑤Use the gastric antrum tissuefor testing the transcriptional level of c-kit mRNA,SCF mRNA by RT-PCRmethod. Results:1. The model validation:(1)General states of the rats: Rats incontrol group were in good state of mind, a flexible action, a good appetite,andthe urine was normal during the experiment. Rats in model group were in badstate of mind, a slowly action, a poor appetite and had a dry stool.(2)The gastricemptying rate of phenol red in control group and model group were:61.76%±1.22%and53.07%±2.19%, The gastric emptying rate in model group was significan--tly lower than control group (p<0.05).2.The results of CAP intervention:(1)General states of the rats: There was no death during the experiment.Rats inGroup A were in good state of mind, a flexible action, a good appetite and theurine was normal. Rats in Group B were in bad state of mind, a slowly action, apoor appetite and had a dry stool. Rats in Group C were in good spirits, a bit slowly action, a good appetite and the urine was normal. Rats in Group D were ingood state of mind, a flexible action, a good appetite and the urine wasnormal.(2)The gastric emptying rate of phenol red in Group A,B,C,D were:62.91%±1.10%,55.33%±1.79%,61.88%±2.07%,70.78%±2.42%.The gastricemptying rate in Group B was Significantly lower than Group A, C,D(p<0.05),the gastric emptying rate in Group A was Significantly lower than GroupD(p<0.05), the gastric emptying rate betwee Group A and Group C had nosignificant differences(p>0.05).(3)The plasma MTL results in Group A,B,C,Dwere:190.30±1.68pg/ml,179.75±1.72pg/ml,200.06±2.06pg/ml,201.37±1.45pg/ml.The plasma MTL in Group B was Significantly lower than Group A,C,D(p<0.05), the levels of plasma MTL in Group A was Significantly lower thanGroup C,D(p<0.05), the plasma MTL betwee Group C and Group D had nosignificant differences(p>0.05).(4)Immunohistochemistry detection results:①Theexpression integral of TRPV1in Group A,B,C,D were:2.30±0.48,2.20±0.42,3.30±0.48,3.60±0.52. The expression of TRPV1in Group A was Significantlylower than Group C,D(p<0.05), the expression of TRPV1in Group B wasSignificantly lower than Group C,D(p<0.05), the expression of TRPV1betweeGroup A and Group B had no significant differences(p>0.05),the expression ofTRPV1betwee Group C and Group D had no significantdifferences(p>0.05).②The expression integral of SP in Group A,B,C,D were:2.00±0.47,1.20±0.42,3.20±0.63,3.50±0.53. The expression of SP in Group B wasSignificantly lower than Group A, C,D(p<0.05), the expression of SP in Group A was Significantly lower than Group C,D(p<0.05), the expression of SP betweeGroup C and Group D had no significant differences(p>0.05).③The expressionintegral of c-kit in Group A,B,C,D were:1.30±0.48,0.80±0.42,1.50±0.53,1.70±0.48. The expression of c-kit in Group B was Significantly lower than Group A,D(p<0.05), the expression of c-kit among Group A,Group C and Group D had nosignificant differences(p>0.05), the expression of c-kit betwee Group B andGroup C had no significant differences(p>0.05), the expression of c-kit betweeGroup C and Group D had no significant differences(p>0.05).(5)Results ofRT-PCR method:①The expression of c-kit mRNA in Group A,B,C,D were:0.624±0.016,0.606±0.011,0.622±0.011,0.633±0.013. The expression of c-kitmRNA in Group B was Significantly lower than Group A, D(p<0.05).Theexpression of c-kit mRNA among Group A,Group C and Group D had nosignificant differences(p>0.05).The expression of c-kit mRNA betwee Group Band Group C had no significant differences(p>0.05).The expression of c-kitmRNA betwee Group C and Group D had no significant differences(p>0.05).②The expression of SCF mRNA in Group A,B,C,D were:0.894±0.011,0.853±0.009,0.932±0.009,0.949±0.012. The expression of SCF mRNA in GroupB was Significantly lower than Group A, C,D(p<0.05), the expression of SCFmRNA in Group A was Significantly lower than Group C,D(p<0.05), theexpression of SCF mRNA betwee Group C and Group D had no significantdifferences (p>0.05).(6)The gastric mucosa injury index and histopathologicalexamination results:①The gastric mucosa injury score (Guth standard modified score) in Group A,B,C,D were:0.40±0.52,2.90±0.74,1.40±0.52,0.50±0.53. Thegastric mucosa injury score in Group B was Significantly higher than Group A,C,D(p<0.05), the gastric mucosa injury score in Group C was Significantlyhigher than Group A, D(p<0.05), the gastric mucosa injury score betwee Group Aand Group D had no significant differences(p>0.05).②The gastric mucosalhistopathological damage integral(Masuda standard method) in Group A,B,C,Dwere:0.30±0.48,3.70±1.89,1.60±0.70,0.40±0.52.The gastric mucosal histopathol--ogical damage integral in Group B was Significantly higher than Group A,C,D(p<0.05), the gastric mucosal histopathological damage integral in Group Cwas Significantly higher than Group A, D(p<0.05), the gastric mucosalhistopathological damage integral betwee Group A and Group D had nosignificant differences(p>0.05).Conclusion:(1)WIRS method could establish ananimal model of gastric motility disorder.(2) The CAP feed for4weeks couldimprove the gastric emptying rate in WIRS rats.(3) The CAP feed for4weekscould improve the gastric emptying rate in normal rats.(4)The mechanism ofCAP act on gastric motility may via regulate the expression of TRPV1,SP and therelease of MTL.(5)CAP may have an effect on the expression of SCF,and have noobvious relationship with interstitial cells of Cajal and c-kit. |
PDF Full Text Request