楹树提取物对大鼠胃溃疡的作用及可能机制

Effect and possible mechanism of Albizia chinensis extract on gastric ulcer in rats

目的评价楹树提取物对大鼠急性胃溃疡的影响并研究其与H^+,K^+-ATP酶(质子泵)相关的作用机制。方法采用水浸拘束和腹腔注射吲哚美辛建立大鼠急性胃溃疡模型,造模前30 min灌胃给予楹树提取物,以溃疡数和溃疡抑制率评价楹树提取物对急性胃溃疡的药效;HE染色观察楹树提取物对胃溃疡组织病理学变化的影响;生化法检测楹树提取物对大鼠离体胃壁细胞H^+,K^+-ATP酶活性的影响;细胞免疫荧光实验法观察楹树提取物对离体胃壁细胞H^+,K^+-ATP酶转位的影响。结果楹树提取物300 mg/kg灌胃对水浸拘束和吲哚美辛致大鼠急性胃溃疡的抑制率分别为70.0%和75.4%。楹树提取物(15、30、60、120、240和480 mg/L)对胃壁细胞H^+,K^+-ATP酶活性的抑制率分别为21.5%、29.4%、44.1%、51.9%、57.7%和62.9%,较空白对照组均具显著差异(均P<0.01),ID50为130 mg/L。但楹树提取物对H^+,K^+-ATP酶的转位无明显影响。结论楹树提取物300 mg/kg对急性胃溃疡有保护作用,抑制H^+,K^+-ATP酶的活性是其作用机制之一。

Objective To investigate the gastric protective effect of Albizia chinensis extract on acute gastric ulcer model in rats and its mechanism related to H＋,K＋-ATPase in gastric parietal cells. Methods Rats were injected intraperitoneally with indometacin or kept under water immersion-restraint stress（WRS）to establish acute gastric ulcer model. Test samples were orally given30 min before induction of gastric ulcer,and the gastric ulcer index and inhibitory rate were used to evaluate the effect of A. chinensis extract. Gastric mucosa pathological tissues in rats were observed by HE staining,the enzymatic activity of proton pump on isolated gastric parietal cells was measured,and the translocation of gastric proton pump was observed by immunofluorescence cell staining.Results The A. chinensis extract inhibited the gastric ulcer with the inhibition rate of 70.0% and 75.4% at 300 mg/kg in the WRS and indomethacin-induced rat model,respectively. The extract could also inhibit the enzymatic activity of gastric proton pump with the inhibition rate of 21.5%,29.4%,44.1%,51.9%,57.7% and 62.9%（P〈0.01）at 15,30,60,120 and 480 mg/L,respectively. The half-effective dosage（ID50）of the extract was determined to be 130 mg/L. The extract showed no significant effect on the translocation of gastric proton pump. Conclusion The A. chinensis extract（300 mg/kg,ig）could significantly prevent the formation of gastric ulcer in rats via inhibiting the enzymatic activity of gastric proton pump.