Study On The Gastrointestinal Function And5-HT Regulatory Mechanisms Of Xiaoyao Powder In Rats Of CUMS Model

Objective:Build the Chronic Unpredictable Mild Stress (CUMS) depression rat model,to observe the effects of xiaoyao powder on the change of gastrointestinal motility and5-HT regulatory mechanisms.Methods:The depression model was replicated by chronic unpredictable mild stress and single cage feeding in rat.Model rats were administrated with Xiaoyao Powder(30g/kg,20g/kg) for4weeks after being accepted stress for2weeks,at the same timg to continue the buliding.and the weight,sweet water consumption of mice and locomotor activity were observed at regular intervals.Evaluate the spatial learning and memory ability of the CUMS model rat was applied with Morris maze test.After being administrated with Xiaoyao Powder for4weeks,gastric emptying rates,small intestine driving action,ball discharge time and AWR values were measured. The contents of Gas,MTL,5-HT,5-HIAA in serum and5-HT,5-HIAA in Colon tissue in rats were detected by ELISA assay.The expressive levels of5-HT3RmRNA and5-HT4RmRNA in Colon tissue of the CUMS depression rats were detected by the method of RT-PCR.The expressive levels of5-HT3R and5-HT4R protein were detected by the method of western-blot.Building the depression model with the same method in rat,the model rats were administrated with Xiaoyao Powder(30g/kg) for4weeks after being accepted stress for2weeks,and observed the behaviors of the model rats.Gastric emptying rates and small intestine driving action were measured.Results:(1)Comparing with the normal group,the weight and locomotor activities of CUMS rats decreased obviously,consumption of a sweet solution and the learning and memory abilities dropped.Prompted behaviors of the CUMS model rats became abnormal,as well as the gastric emptying rates and small intestine pushing rates of the CUMS model rats were decreased,ball discharge time and AWR values were significantly reduced,the gastrin and motilin contents in serum were also decreased in model group.Prompted the gastrointestinal function of the CUMS model rats performanced disorder.Besides,the contents of5-HT,5-HIAA in serum and Colon tissue were dropped,the expression of mRNA and protein of5-HT3R/5-HT4R in Colon tissue were dropped.Prompted the neural function of5-HT in Colon tissue of the CUMS model rats showed abnormal.(2) Comparing to the CUMS depression model group,After being administrated with Xiaoyao Powder (30g/kg,20g/kg) for4weeks,the abnormal of the weight,the locomotor activities,the consumption of a sweet solution, the learning and memory abilities were improved obviously,the gastric emptying rates and small intestine pushing rates of the CUMS model rats were improved,the time of ball discharge and AWR values were increased,and exhibit the increasing trend on the level of gastrin and motilin in serum,the contents of5-HT,5-HIAA in serum and Colon tissue were improved,and the relative expression level of mRNA and protein of5-HT3R/5-HT4R in Colon tissue.(3) Comparing with the normal group,the weight and locomotor activities of the model rats decreased obviously,consumption of a sweet solution dropped,the gastric emptying rates and small intestine pushing rates were decreased.Comparing to the CUMS depression model group,the group of xiaoyao powder(30g/kg)could confronted the abnormal of the behaviors and the gastrointestinal motility of the ratConclusion:Xiaoyao-powder showed the good effects to CUMS depression rats in changing the abnormal ethology and gastrointestinal function,showing that it has good antidepressant effect,thereinto,the anti-gastrointestinal dysfunction effects has played a role of antidepressant mechanism,and it’s mechanism would be related to regulating the level of gastrointestinal hormones and the function of5-HT System.