阴离子交换蛋白2功能异常对结肠分泌及蠕动功能的影响

Effects of dysfunction of anion exchanger 2 on secretion and peristalsis of colon

目的探讨阴离子交换蛋白2(AE2)功能异常对结肠黏膜上皮细胞分泌功能及肠管蠕动功能的影响。方法通过复方地芬诺酯灌胃建立SD大鼠便秘模型(模型组,n=17),以未建模SD大鼠作为对照(对照组,n=28)。体外分离培养大鼠结肠黏膜上皮细胞,单细胞离子成像技术比较两组大鼠结肠黏膜上皮细胞培养液中加入AE2抑制剂DIDS前后pH变化值。利用Powerlab系统及Chart5软件绘制离体肠管蠕动曲线,比较两组大鼠离体肠管的蠕动幅度和频率,评价肠管蠕动功能。通过急性滴加试验观察和比较在对照组离体肠管培养液中滴加AE2抑制剂DIDS前后肠管蠕动功能的变化。结果单细胞离子成像技术检测显示,结肠黏膜上皮细胞培养液中加入DIDS后,模型组细胞内pH值继续升高,与加入DIDS后对照组细胞内pH值比较差异有统计学意义(P<0.01)。肠管蠕动曲线观测显示,模型组大鼠离体结肠平滑肌蠕动幅度和频率均明显低于对照组(P<0.05或P<0.01);急性滴加试验表明,培养液中滴加DIDS后,对照组离体结肠平滑肌蠕动幅度和频率均显著降低(P<0.05或P<0.01)。结论 AE2离子转运活性下降可导致结肠分泌功能紊乱及蠕动功能障碍。

Objective To investigate the effects of dysfunction of anion exchanger 2 （AE2） on secretion of epithelial cells of colon mucosa and intestinal peristalsis. Methods SD rat constipation models were established by intragastric administration of diphenoxylate compound （model group, n=17）, and SD rats without model establishment were served as controls （control group, n=28）. Rat epithelial cells of colon mucosa were isolated and cultured in vitro, changes of pH after adding AE2 inhibitor DIDS into culture fluid of epithelial cells of colon mucosa were compared between model group and control group with single cell ion imaging. Curves of in vitro intestinal peristalsis were drawn with Powerlab System and Chart 5 Software, amplitudes and frequencies of in vitro intestinal peristalsis were compared between groups, and intestinal peristalsis function was evaluated. The changes of intestinal peristalsis function after adding AE2 inhibitor DIDS into culture fluid of in vitro intestine in control group were observed and compared with fast adding test. Results Single cell ion imaging revealed that pH in model group increased after addition of DIDS into culture fluid of epithelial cells of colon mucosa, and was significantly different from that in control group after addition of DIDS （P〈0.01）. It was obtained from curves of intestinal peristalsis that the amplitude and frequency of in vitro colon smooth muscle peristalsis in model group were significantly lower than those in control group （P〈0.05）, and fast adding test indicated that the amplitude and frequency of in vitro colon smooth muscle peristalsis in control group significantly decreased after addition of DIDS into culture fluid （P〈0.05）. Conclusion The dysfunction of AE2 may result in the disorder of secretion and peristalsis of colon.