The Effects Of Polysaccharide Oyster On Digestive Tract Of Mouse Under Heat Stress Condition

The purpose of these experiments are to study the effects of oysterpolysaccharides on heat-stressed mouse gastrointestinal tract:the structure, absorptivecapacity, immunity capacity, antioxidant capacity,and endocrine hormones, such asgastrin(Gas), motilin(MTL), Somatostatin(SS), cholecystokinin(CCK) and substanceP(SP). Experiments are as follows:1The effects of oysters polysaccharide on Gastrointestinal mucosal antioxidantcapacity and enzymes in heat-stressed mouse.30SD mice, male-adulted,were divided into five groups randomly, control group,heat-stressed group, high,middle,low dose polysaccharides treated group. The controlgroup and heat-stress ed group were fed the normal diet;the high,middle,low dosepolysaccharides treated group were given oysters polysaccharide0.9,0.6,0.3g per100g normal feed, continuously feeding21d. From22d, the heat-stressed group,high,middle,low dose polysaccharides group were treated at38℃,45min and then42℃,20min, continuously7days.After the last heat stress, mice were broken neck todeath. Quickly getting gastrointestinal tissue to homogenate and centrifuge to obtainsupernatant. Then the total antioxidant capacity (T-AOC), total glutathione(T-GSH/GSSG), acid phosphatase (ACP) and lysozyme were measured. Results:Under heat stress,the oyster polysaccharides can significantly increase totalglutathione levels in the mouse gastrointestinal tissues, there is an increasing trend inlysozyme activity and total antioxidant capacity. Conclusion: Oysters polysaccharidecan enhance the antioxidant capacity and improve the level of enzymes of theheat-stressed mouse gastrointestinal tissue.2The effects of oysters polysaccharide on the stucture and absorption power ofgastrointestinal tract in heat-stressed mouse.The methods as above. Then the mice were broken neck to death quickly toobtain the duodenum, jejunum.After fixation, dehydration, transparence, embedment, section and stain, the villus length, crypt depth and absorption power were measured.Results: Under heat stress, the oysters polysaccharide can significantly improve thelevel of serum D-xylose and increase gastrointestinal villus height, crypt depth, villusheight and crypt depth ratio (V/C).Conclusion: Oyster polysaccharide can maintainthe normal structure of gastrointestinal tract and improve intestinal absorption powerto improve the heat-stressed mouse intestinal function.3The effects of oysters polysaccharide on the Gastrointestinal hormons inheat-stressed mouse.45SD mice, male-adulted,were divided into three groups randomly, controlgroup, heat-stressed group, polysaccharide group. The control group and heat-stressedgroup were fed the normal diet; the polysaccharide group was given oysterspolysaccharide0.9g per100g normal feed, continuously feeding21d. From22d, theheat-stressed group, polysaccharide group were treated at38℃,45min and then42℃,20min, continuously7days.After the last heat stress, mice were broken neck todeath to get gastrointestinal tissue quickly.Put the tissue tofix,dehydrate,trasparent,embed,section,stain.The immunohistochemical localization ofGastrointestinal hormone of mice were studied with mammal serumi．e．anti-Gastrointestinal hormone by the immunohistochemical technique of thestreptavidin—peroxidase marked with HRP．Results: The levels of gastrin andsomatostatin decline in fundic,while rise in duodenum; the levels of motilin andcholecystokinin decline,while substance P rises in the entire gastrointestinaltract.Conclusion: In the state of heat stress, oysters polysaccharide can decreasegastrin,somatostatin levels in fundus of heat-stressed mice, while increase the gastrin,somatostatin levels in the duodenum; oysters polysaccharide can decrease motilin,cholecystokinin levels,but increase substance P level in gastrointestinal tract to helpalleviate the impact of heat stress on animals adjustment function.