丝裂霉素C对兔眼睫状体无色素上皮细胞的毒性作用

Cytotoxic effect of mitomycin C on the nonpigmented epithelium of ciliary body in rabbit eyes

目的观察兔眼巩膜咬切术中应用０．２ｍｇ／ｍｌ丝裂霉素Ｃ（ＭｉｔｏｍｙｃｉｎＣ，ＭＭＣ）后，睫状体无色素上皮细胞的病理形态学的改变，探讨ＭＭＣ对睫状体的毒性作用。方法在兔眼巩膜咬切术中用含０．２ｍｇ／ｍｌ的ＭＭＣ０．１ｍｌ的海绵块，置于Ｔｅｎｏｎ囊和巩膜之间共５分钟，并用２０ｍｌ生理盐水冲洗，术后第７及２８天，采用光镜观察睫状体，透射电镜观察其无色素上皮细胞。结果术后第７天睫状体无色素上皮细胞水肿，线粒体丰富、肿胀、空泡化，β细胞膜间隙出现有膜包绕的囊泡，呈串珠样排列。术后第２８天，以上损害明显减轻。结论ＭＭＣ对无色素上皮细胞有毒性作用，由此可能导致房水分泌减少，眼压下降。

Objective To observe pathomorphological changes of nonpigmented epithelial cells (NECs) of ciliary body after local single application of mitomycin C (MMC) during sclerectomy in rabbit eyes, and to explore cytotoxic effect of MMC on ciliary body. Methods A single five minutes intraoperative exposure to the agent MMC (0.2 mg/ml, 0.1 ml) was used during sclerectomy in rabbit eyes. The treated area was rinsed with 20 ml normal saline. The NECs of ciliary body at the operated area were observed under light microscope and transmission electron microscope on the 7th and 28th day postoperatively. Results On the 7th day postoperatively, the NECs were swollen, and the intracellular abundant mitochondria were swollen and vacuolized. String pearls like membrane encapsulated vacuoles were present in the intervals of β cell membrane of the NECs. On the 28th day postoperatively, these damages were gradually recovered. Conclusions These findings suggest a toxic effect of MMC on the NECs of ciliary body, possibly that can decrease the aqueous production and intraocular pressure, even causing persistent hypotony.