鼠溃疡性结肠炎模型的观察

Observation of experimental model of ulcerative colitis in rats

目的评价胎鼠结肠植入同系成年鼠所致溃疡性结肠炎（ＵＣ）模型．方法将胎鼠结肠植入同系鼠肾包膜下，观察胎鼠结肠和成年鼠结肠的组织学变化，并且采用微量细胞毒方法检查心脏血淋巴细胞或肠粘膜淋巴细胞对自身结肠上皮细胞的细胞毒指数．结果胎鼠结肠成功地植入２７只同系成年鼠的肾包膜下，７ｄ后植入的胎鼠结肠出现免疫排斥反应，表现为粘膜炎症和溃疡形成．还观察到宿主鼠结肠的自身免疫反应，表现为淋巴滤泡增多和炎性细胞浸润．２７只实验鼠的心脏血淋巴细胞或结肠粘膜淋巴细胞对自身结肠上皮细胞的细胞毒指数分别为４１６％±３８％，３８４％±２１％，而１５只正常对照鼠的相应指数分别为８２％±１９％，７０％±１７％，两者间的差异有显著性意义（Ｐ＜００１）．结论胎鼠结肠植入同系成年鼠能导致类似于ＵＣ的变化。

IM To evaluate the ulcerative colitis model of fetal colon implants in syngenic adult rats. METHODS Implant the fetal colon into renal capsule of syngenic adult rats and observe the histologic changes of the colon and the cytotoxicity index of cardiac blood lymphocytes or colonic mucosal lymphocytes against autologous colonic epithelial cells in experimental rats by the microcytotoxicity method. RESULTS When the fetal colon was successfully implanted under renal capsule in 27 syngenic adult rats, the immunorejection occurred in the implanted fetal colon after 7 days by mucosal inflammation and ulceration. Autoimmune reaction was also observed in the colon of the recipient rats by the increase of lymphoid follicles and infiltration of inflammatory cells. The cytotoxicity index of cardiac blood lymphocytes or colonic mucosal lymphocytes against autologous colonic epithelial cells was 416%±38% or 384%±21% vs 82%±19% or 7%±17% in 27 experimental rats and 15 rats of normal controls (P<001, respectively). CONCLUSION Implantation of fetal colon into the renal capsule of syngenic adult rats can reduce colonic inflammation similar to human ulcerative colitis and the cytotoxicity of lymphocytes against autologous colon may play an important role in cellular immune reaction.