Based On Brain-intestinal Interaction, The Therapeutic Effect And Peripheral Mechanism Of Spider Scented Iridoids ZXY On IBS Model Rats Were Studied

Irritable bowel syndrome(IBS)is a group of persistent or intermittent seizures,abdominal pain,abdominal distension,bowel habits and(or)stool changes of intestinal function disorder as the main clinical manifestations.It is characterized by abdominal pain and(or)discomfort and disordered bowel habits.The main categories of constipation(IBS with constipation,IBS-C),diarrhea(IBS with diarrhea,IBS-D),mixed type(mixed IBS,IBS-M)and unsubtyped(IBS-U),IBS-D is the more common type in clinical.IBS is one of the most common gastrointestinal diseases,which has become a global disease,the prevalence rate as high as 10-20%;in China,the incidence rate of Beijing is 7.26%.The clinical course of IBS is long,symptoms of recurrent seizures,accounting for more than 50%of the number of outpatient department of Gastroenterology.It bring great economic and mental burden to the community and the family to.However,the existing researches on the pathogenesis of IBS are not completely clear.Except abnormal intestinal motility,visceral hypersensitivity and other traditional views in the physiological and pathological,new discoveries and researches progress are important in many other ways.As a kind of non organic disease,IBS is mainly composed of antispasmodic,antidiarrheal,antidepressant and gastrointestinal micro ecological agents.However,there are many side effects and shortcomings of Western medicine,which is less than traditional Chinese medicine.Traditional Chinese medicine is the first choice for the treatment of non organic lesions,and it is widely used in IBS-D.At present,the researches on the treatment of IBS-D drugs include single herb and compound Chinese medicine,and the effect is obvious.Valerianae Jatamansi Rhizoma et Radix sweet known as Patrinia herb(Valeriana jatamansi Jones)v.jatamansi dried rhizome and roots,is contained in "China Pharmacopoeia"2015 Edition(a),which taste bitter,acrid,warm heart,spleen and stomach.The main efficacy:Qi and relieve pain,help to digest and antidiarrheal,Qufengchushi,calm nerves.As one of the main varieties of Miao medicine,it is a common herbal medicine in Yunnan province.It mainly used in the clinical treatment of abdominal distention,dyspepsia,diarrhea,dysentery,rheumatism,insomnia and other symptoms.The preliminary experimental results show that both the original powder and iridoid effective parts could reduce the visceral sensitivity of IBS rat model caused by chronic stress,significantly reduce the amount of defecation in IBS model rats,improve the mental state.In addition,the effective part of the iridoid can reduce the peripheral,increase the content of central 5-HT,reduce the expression of 5-receptor 3(5-HT3)in the colon,thus improving the gastrointestinal symptoms of IBS model rats.It has been proved that the active part of the iridoid can improve the symptoms of IBS by intervening the peripheral and central 5-HT pathway.ZXY is the main component of v.jatamansi iridoids after degradation,its chemical name is baldrinal.Previous researches showed that:ZXY had antidiarrheal effect on stress and diarrhea model of mice and the diarrhea model mice,and the treatment effect is better than the latter.It can significantly improve diarrhea and spirit the effect of abnormal state of mice caused by reserpine.Objective:To investigate the therapeutic effects of ZXY on IBS and the peripheral mechanism,this subject will evaluate the therapeutic effect of ZXY on IBS through the observation of the effect of ZXY on visceral sensitivity,defecation,mental activity changes of IBS model rats caused by chronic-acute stress;explore the peripheral mechanism of the function through the determination the expression of corticotropin releasing factor(CRF)and tryptophan hydroxylase 1mRNA(TPH1mRNA),5-(5-HT)and serotonin receptor and mast cell(MC)and protease activated receptor 2(PAR2)in the colon of IBS model rats.Methods:1.Establishment of IBS rat model induced by chronic-acute stress:120 to 140g SD male rats were randomly divided into control group,IBS model group,ZXY large,medium and small dose group(0.6mg/kg,0.3mg/kg,0.15mg/kg)and fluoxetine group(2.5mg/kg),pinaverium bromide group(25mg/kg)and ondansetron group(1.8mg/kg).The rats in the model groups and the drug groups were treated with 1 rat in each cage,and were subjected to chronic-acute unpredictable stimulation.The first 21 days were given the chronic stress,and then after the termination of chronic stress for 1 week,the rats were given acute stress constraint 1h.Chronic stress included:fasting,water deprivation,night,cold stimulation,wet feeding,hurt and brake.7 kinds of stimulating factor were arranged randomly one day,and each stimulus can not be continuous,so that rats cannot anticipate stimulation.The rats in each ZXY dose groups and positive drug groups were given intragastric administration for thirty-fourth day,the control group and the model group were given distilled water,and the drug was given for 35 days.The changes of visceral sensitivity and gastrointestinal function were evaluated by abdominal retraction reflex score(AWR),fecal score and body weight gain rate.2.Effects of ZXY on visceral sensitivity and gastrointestinal function in IBS rats:Determine the experimental rats with AWR score before the start of the experiment and experiment of 14,27,41,55,65 days;fecal rats score before the start of the experiment and experiment of 25,54 and 68 days;weight growth rate before the experiment and experiment of 13,25,37,52,69 days;before the experiment and experiment 24,32,58,69 days of experiment rats sucrose preference.3.Use the acetic acid writhing test to determine the effects of ZXY on mice abdominal pain.4.CRF in the colon of rats was determined by the immunohistochemical ation;TPH1mRNA in the colon of rats was determined by PCR methods;5-HT and 5-HIAA were determined by high performance liquid chromatographyhigh;5-HT1A,5-HT3,SERT were determined by Western Blot;MC were determined by staining toluidine blue colon quantity;expression of PAR2 in colon were determined by Western Blot.Results:The experimental results showed:1.Before the experiment,there was no significant difference in AWR score,rats feces score and body weight growth rate(P>0.05);after modeling,the rats in the model group AWR score and fecal score was significantly higher than the control group(P<0.05),the growth rate of body weight was significantly lower than in control group(P<0.05);after ZXY dose treatment,AWR score and fecal score of each treatment group were significantly lower than those in the model group(P<0.05),ZXY high dose group weight growth rate was significantly higher than that in the model group(P<0.05).Before the experiment and experiment 24,32,58,69 days of experiment rats sucrose preference,the results indicated that before the experiment the rats sucrose preference was not significant difference(P>0.05),after modeling in rats of model group preference decreased(P<0.05),after drug treatment in the treatment group sucrose preference was significantly increased(P<0.05).2.Results showed that ZXY medium dose can significantly improve the pain threshold of mice(p<0.05);ZXY medium dose and large dose can reduced writhing times within 20 minutes(p<0.05).3.The results showed that the expression of CRF,TPH1mRNA,5-HT and 5-HT3A in colon of rats in model group was significantly higher(P<0.05),and the expression of 5-HT1A and SERT in colon was significantly lower(P<0.05).The CRF expression of ZXY high dose group was significantly decreased compared with the model group(P<0.05).Small dose can significantly reduce the expression of TPH1mRNA in colon of rats(P<0.05).Each group can reduce the content of 5-HT and 5-HIAA in the colon(P<0.05).High dose and medium dose of ZXY can effectively improve the expression of 5-HT1A(p<0.05);large,medium and small dose of ZXY could be reduced the protein expression of 5-HT3A in the colon(p<0.05);high dose of ZXY can improve the protein expression of SERT in colon(p<0.05).4.MC were determined by staining toluidine blue colon quantity;expression of PAR2 in colon were determined by Western Blot.The experimental results showed that MC in the colon of rats in the model group and the expression of PAR2 were significantly increased(P<0.05);ZXY high and medium dose can significantly reduce the number of colonic MC(P<0.05),the expressions of PAR2 in ZXY groups were significantly decreased compared with the model group(P<0.05).Conclusion:In this subject,the changes of visceral sensitivity and gastrointestinal function were evaluated by abdominal retraction reflex score(AWR),fecal score and body weight gain rate,and the degree of abdominal pain was judged by writhing method,which were the clear indexes in pharmacodynamics.The results showed that:in the case of isolated,IBS rat model can be successfully established with water deprivation,fasting,day and night reversal,cold stimulation,wet feeding,pain,and restraint combined with acute restraint.It is studied the ZXY may ameliorate the visceral hypersensitivity,gastrointestinal dysfunction and abnormal mental activity in IBS rats induced by chronic-acute stress.The mechanism of action may be through regulating the colon 5-HT pathway and affecting the colon MC and PAR2.Through this subject,the researches provide the experimental basis for the study of the material basis and mechanism of the treatment of IBS,and provide a new idea for the clinical drugs of IBS.