生白术多糖对洛哌丁胺诱导大鼠便秘的改善作用研究

目的 探究生白术多糖对洛哌丁胺诱导大鼠便秘的改善作用及机制。方法 采用ig洛哌丁胺（3mg/kg）复制便秘大鼠模型，给予生白术水、醇提物及生白术多糖，通过测定粪便含水率、12h粪便粒数及小肠推进率等指标评价其治疗便秘的作用；采用ELISA法检测大鼠血浆中胃动素（motilin，MTL）及血管活性肠肽（vasoactive intestinal peptide，VIP）水平；采用苏木素-伊红（HE）染色法检测大鼠结肠组织病理变化；采用免疫组化法检测结肠组织中黏蛋白2（mucoprotein 2，MUC2）和闭锁小带蛋白-1（zonula occludens-1，ZO-1）蛋白表达。结果 生白术水提物显著改善便秘导致的大鼠粪便含水率、12h粪便粒数及小肠推进率降低等症状（P＜0.01、0.001），而生白术醇提物则无明显改善作用。生白术多糖显著改善便秘大鼠症状（P＜0.001），显著升高便秘大鼠血浆中MTL水平并降低VIP水平（P＜0.001），改善便秘大鼠结肠黏膜损伤及杯状细胞的减少，显著增加便秘大鼠结肠组织MUC2和ZO-1的蛋白表达（P＜0.05、0.001）。结论 生白术水提物治疗便秘药效显著，多糖是其治疗便秘的活性组分，可能通过调节血浆MTL、VIP水平，增加结肠组织MUC2、ZO-1蛋白表达水平，从而促进胃肠蠕动并增强结肠黏膜屏障功能，改善便秘症状。

Ameliorative effect of polysaccharides from raw Atractylodes macrocephala on constipation induced by loperamide in rats

Objective To explore the effect and mechanism of polysaccharides from raw Baizhu (Atractylodes macrocephala) on constipation induced by loperamide in rats. Methods The rat model of constipation was made by ig loperamide (3 mg/kg), and the water, ethanol extract and polysaccharides from raw A. macrocephala were given. The effects of rat model on constipation were evaluated by measuring fecal water content, number of fecal particles in 12 h and rate of intestinal propulsion; The levels of motilin (MTL) and vasoactive intestinal peptide (VIP) in plasma of rats were detected by ELISA; HE staining was used to detect the pathological changes of colon tissue in rats; The expressions of mucoprotein 2 (MUC2) and zonula occludens-1 (ZO-1) in colon tissue were detected by immunohistochemistry. Results The water extract from raw A. macrocephala could significantly improve the symptoms such as decreasing of fecal water content, fecal grains in 12 h and intestinal propulsion rate in rats caused by constipation (P<0.01, 0.001), ethanol extract had no obvious improvement effect. Polysaccharides from raw A. macrocephala significantly improved the symptoms of constipation rats (P<0.001), increased MTL and decreased VIP levels in plasma (P<0.001), improved the damage of colon mucosa and reduction of goblet cells in rats with constipation, significantly increased the protein expressions of MUC2 and ZO-1 in colon tissues of rats with constipation (P<0.05, 0.001). Conclusion The water extract from raw A. macrocephala has a significant effect on constipation. Polysaccharides are the active components in treatment of constipation. It may increase the expressions of MUC2 and ZO-1 proteins in colon tissue by regulating MTL and VIP levels in plasma, thereby promoting gastrointestinal peristalsis, enhancing the barrier function of colon mucosa, and improving constipation symptoms.