橘皮竹茹汤对化疗性异食癖大鼠模型5-羟色胺3受体蛋白和mRNA表达的影响

Effects of Jupi Zhuru Decoction on expression of 5‑HT3R protein and mRNA in chemotherapy‑induced pica rats

目的观察橘皮竹茹汤对化疗性异食癖大鼠模型止呕作用及对5-羟色胺3受体(5-HT3R)蛋白和mRNA的影响。方法将36只Wistar雄性大鼠随机分为正常对照组、中药对照组(橘皮竹茹汤10.6 g/kg,不造模)、模型组、昂丹司琼组(2.6 mg/kg)、橘皮竹茹汤低剂量组(5.3 g/kg)和橘皮竹茹汤高剂量组(10.6 g/kg),每组6只。各组大鼠给予相应干预措施6 d(每日2次)后,采用腹腔注射顺铂(6 mg/kg)的方式诱导建立化疗性异食癖大鼠模型,观察并记录造模后24 h内大鼠体质量、摄食量和高岭土摄入量的变化。继续干预1 d后,苏木精-伊红(HE)染色观察各组大鼠胃窦、回肠组织形态学变化;实时荧光定量逆转录聚合酶链式反应(RT-qPCR)法检测延髓、回肠组织中5-HT3R、色氨酸羟化酶(TPH)、单胺氧化酶A(MAOA)mRNA表达;Western blot法检测延髓组织中5-HT3R蛋白的表达。结果①与正常对照组比较,模型组大鼠体质量、摄食量降低(P<0.05),高岭土摄入量显著增加(P<0.05);与模型组比较,昂丹司琼组和橘皮竹茹汤低、高剂量组大鼠高岭土摄入量显著降低(P<0.05)。②HE染色显示,与正常对照组比较,模型组胃窦组织上皮细胞受损,固有层腺体排列疏松、紊乱,回肠上皮部分缺失,腺体排列紊乱;与模型组比较,昂丹司琼组和橘皮竹茹汤低、高剂组胃窦和回肠组织病理改变减轻。③RT-qPCR结果显示,与正常对照组比较,模型组大鼠延髓、回肠5-HT3R mRNA表达水平显著升高(P<0.05),回肠MAOA mRNA表达水平显著降低(P<0.05);与模型组比较,橘皮竹茹汤高剂量组大鼠延髓5-HT3R mRNA表达水平明显降低(P<0.05),橘皮竹茹汤低剂量组回肠TPH1 mRNA、橘皮竹茹汤高剂量组延髓TPH2 mRNA表达水平明显降低(P<0.05),昂丹司琼组、橘皮竹茹汤低剂量组、橘皮竹茹汤高剂量组回肠MAOA mRNA表达水平明显升高(P<0.05)。④Western blot结果显示,与正常对照组比较,模型组大鼠延髓5⁃HT3R蛋白表达水平显著升高(P<0.05);与模型组比较,橘皮竹茹汤高剂量组大鼠延髓5-HT3R蛋白表达水平显著降低(P<0.05)。结论橘皮竹茹汤可以通过抑制延髓5-HT3R蛋白和mRNA的表达,调控5-羟色胺合成与代谢相关酶,进而改善化疗导致的恶心呕吐。

Objective To observe the antiemetics effects of Jupi Zhuru Decoction and the expression of 5-hydroxytryptamine 3 receptor(5-HT3R)protein and mRNA in chemotherapy-induced pica rats.Methods Thirty-six Wistar male rats were randomly divided into normal control group,Jupi Zhuru Decoction control group(10.6 g/kg,no modeling),model group,ondansetron group(2.6 mg/kg),Jupi Zhuru Decoction low dose group(5.3 g/kg)and high dose group(10.6 g/kg),with 6 rats in each group.The rats in each group were given corresponding interventions for 6 d(twice a day),and then the chemotherapeutic pica rat model was induced by intraperitoneal injection of cisplatin(6 mg/kg).The changes of body mass,food intake and kaolin intake were recorded within 24 h after modeling.The intervention was continued for 1 d, then the morphological changes of gastric antrum and ileum of rats in each group was observed by hematoxylin-eosin (HE) staining.The expression of 5-HT3R, tryptophan hydroxylase(TPH),monoamine oxidase A(MAOA) mRNA in medulla oblongata and ileum were detected by real-time fluorescent quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR). The 5-HT3R protein in medulla oblongata was detected by Western blot. Results ①Compared with the normal control group, the body mass and food intake of the model group were significantly decreased (P<0.05), and the kaolin intake was significantly increased (P<0.05);the kaolin intake of ondansetron group and Jupi Zhuru Decoction low dose and high dose groups were significantly decreased than that of the model group (P<0.05). ②HE staining results showed that compared with the normal control group, the gastric antrum tissue epithelial cells were damaged and the arrangement of lamina propria glands were loose and disordered, the epithelium of ileum was absent and the glands disordered in model group;compared with the model group, the pathological changes of gastric antrum and ileum in ondansetron group and Jupi Zhuru Decoction low dose and high dose groups were alleviated. ③RT-qPCR results showed that compared with the normal control group, the expressions of 5-HT3R mRNA in the medulla oblongata and ileum of rats in model group were increased (P<0.05),the expression of MAOA mRNA in the ileum was significantly decreased (P<0.05);compared with the model group, the expression of 5-HT3R mRNA in the medulla of rats in the Jupi Zhuru Decoction high dose group was significantly decreased (P<0.05), the expression of TPH1 mRNA in the ileum of Jupi Zhuru Decoction low dose group and TPH2 mRNA in the medulla of Jupi Zhuru Decoction high dose group was significantly decreased (P<0.05), the expression of MAOA mRNA in the ileum of ondansetron group and Jupi Zhuru Decoction low dose and high dose groups were significantly increased (P<0.05). ④Western blot results showed that compared with the normal control group, the 5-HT3R protein in the medulla oblongata of rats in the model group were significantly increased (P<0.05);compared with the model group,5-HT3R protein in the medulla oblongata of rats in the Jupi Zhuru Decoction high dose group were significantly decreased (P<0.05). Conclusion Jupi Zhuru Decoction can improve chemotherapy-induced nausea and vomiting by inhibiting the expression of 5-HT3R protein and mRNA in medulla oblongata, regulating the enzymes related to 5⁃hydroxytryptamine synthesis and metabolism.