糖皮质激素对大鼠肠屏障功能的损害

目的探讨器官移植术后早期应用大剂量糖皮质激素对肠屏障功能的影响。方法将56只Wistar大鼠随机分为免疫抑制组和阴性对照组。免疫抑制组大鼠每日腹腔注射甲泼尼龙100mg/kg,1次/d,阴性对照组每日腹腔注射生理盐水1ml。用药后,每组在全麻下按4个时间点(0、3、5、7d)无菌操作获取血液、肠系膜淋巴结、肠内容及回肠组织,分别用于检测血浆D乳酸、血浆二胺氧化酶(DAO)、肠道菌群微生态、肠系膜淋巴结淋巴细胞凋亡指数及某些脏器细菌培养等。结果免疫抑制组与阴性对照组比较,从用药后第3d开始,各时间点血浆D乳酸以及DAO均显著升高(P<0.01或P<0.05),肠道菌群却无明显改变(P>0.05),肠系膜淋巴结淋巴细胞凋亡指数显著升高(P<0.01);第7d时脏器细菌培养阳性率较阴性对照组明显升高(P<0.05)。结论甲泼尼龙能够造成大鼠肠屏障功能的损害,使肠屏障通透性升高。

Effect of glucocorticoid on rat intestinal barrier function

Objective To investigate the changes of gut barrier function under glucocorticoid, so as to understand the reasons of gut-derived infection and bacteria infection.Methods Fifty-six Wistar rats were divided into control and methylprednisolone (Mep, 100 mg/kg, i.p., once every day) groups, and there were four time points in each group (0, 3, 5, 7 day). At each time point the rats were subjected to general anaesthesia and blood, mesenteric lymph nodes, enteric content and ileal tissue were obtained for determination of serum D-lactic, DAO, intestinal microecosystem, apoptosis index of mesenteric lymph nodes and bacterial culture. Results At the latter three time points, compared with control group, serum D-lactic and DAO, and apoptosis index of mesenteric lymph nodes in MeP group were significantly increased (P< 0.01 or P< 0.05), but gut flora had no significant change (P> 0.05) from the day 3 after administration,the positive rate of organs bacterial culture in MeP groups at the No7 day is much higher than that in control group(P< 0.05). Conclusion The results suggested that glucocorticoid could damage intestinal barrier, and increase its permeability, maybe this is one of the reasons of gut-derived infection .