Effect Of Shengyang Yiwei Decoction On Irritable Bowel Syndrome In Rats Based On "Brain-gut Axis"

Objective: Investigating the effect of Shengyang Yiwei Decoction on level changes of brain-gut peptides in diarrhea-predominant irritable bowel syndrome(IBS-D)rats from the perspective of "brain-gut axis”,exploring the regulation mechanism of Shengyang Yiwei Decoction on the "brain-gut axis" of IBS-D rats.Methods: 60 healthy male SD rats were randomly divided into blank group,model group,positive drug control group,Shengyang Yiwei Decoction high-dose group,Shengyang Yiwei Decoction middle-dose group,and Shengyang Yiwei Decoction low-dose group.Except for the blank group,the other rats were given senna leaf gavage combined with restraint stress and tail clip stimulation to establish the IBS-D model,and the modeling time lasted 14 days.After successful modeling,Shengyang Yiwei Decoction high,medium and low dose groups were administered with corresponding concentrations of Shengyang Yiwei Decoction respectively,the positive drug control group was administered with pinaverium bromide suspension,the model group and the blank group were administered by admini stration equal volume of normal saline.The gavage time lasted 14 d.One hour after the last intragastric administration on the 28 th day,the rats were measured for body weight,abdominal withdrawal reflex(AWR),and using ELISA to detect the contents of 5-HT,SP and VIP in the colon and hypothalamus of the rats in each group;HE staining was used to observe the histological changes of the colonic mucosa of the rats in each group.RESULTS:(1)Before modeling,there were no significant differences in the mental state,defecation,and fur color of the rats in each group;after modeling,compared with the rats in the blank group,the rats in the modeling were lethargic and had loose or loose stools.They liked to get together,were sensitive to external stimuli,and their body weight growth slowed down significantly(P<0.01).After the drug intervention,the weight gain of Shengyang Yiwei Decoction high-dose,medium-dose and low-dose groups and the positive drug control group was higher than that of the model group,the difference was not statistically significant(P>0.05).(2)After the modeling,compared with the blank group,the AWR score of the modeling group was significantly increased(P<0.01),indicating that the modeling rats exhibited high visceral sensitivity;After the drug intervention,compared with the model group,the AWR scores of Shengyang Yiwei Decoction high,medium and low dose groups and the positive drug control group were significantly decreased(P<0.01).(3)Compared with the blank group,the contents of 5-HT,SP and VIP in the colon and hypothalamus of the model group were significantly increased(P<0.05,P<0.01).The contents of 5-HT,SP,and VIP in the high,medium and low dose groups of Shengyang Yiwei Decoction and the positive drug control group were significantly decreased(P<0.01),suggesting that each dose group of Shengyang Yiwei Decoction can reduce the contents of IBS-D rats’ braingut peptide 5-HT,SP,VIP;(4)HE staining observation: there are more lymphocytes in the colonic interstitium of rats in the model group and the positive drug control group,and a small amount of lymphocytes in the colonic interstitium of the other groups,no other pathological changes,in line with the pathological characteristics of irritable bowel s yndrome.Conclusion: Shengyang Yiwei Decoction groups can improve the general condition and body weight loss of IBS-D rats,effectively reduce the sensitivity of internal organs,and significantly reduce the contents of 5-HT,SP and VIP in colon and hypothalamus tissue.The regulation mechanism of Shengyang Yiwei Decoction on the "brain-gut axis" of IBS-D rats may be realized by reducing the contents of peptides in colon and hypothalamus.