中文摘要：

目的:观察N-甲基-N-亚硝脲(N-methyl-N-nitrosourea,MNU)对SD大鼠视网膜光感受器细胞的毒性作用。方法:雌性SD大鼠100只,分17组,正常对照组4只,其余组各6只。在大鼠生后50 d,分别一次腹腔注射MNU 50 mg／kg、60 mg／kg、70 mg／kg和80 mg／kg。在MNU处理后24、48、72 h和7 d处死大鼠,取眼球,做组织学检查。结果:不同剂量的MNU均引起中心视网膜和周边视网膜损伤,其损害的程度与MNU的剂量呈正比。作用24 h后,可见视网膜光感受器细胞核固缩、破坏及光感受器外节部定向紊乱;48 h或72 h后,可见光感受器细胞丧失;7 d后,外颗粒层和光感受层几乎完全消失。结论:MNU对大鼠视网膜光感受器细胞有选择性的毒性作用,该作用呈剂量和时间依赖性。

英文摘要：

Purpose: To observe the toxic effect of N-methyl-N-nitrosourea ( MNU ) on photoreceptor cells within retina of SD rats.Methods: At 50 days of age, 100 female rats received a single intraperitoneal injection of MNU at different doses of 50 mg/kg, 60 mg/kg, 70 mg/kg and 80 mg/kg body weight, respectively. Each group had 6 rats and 4 untreated rats were used as normal control. At 24, 48 and 72 hours and 7 days after the administration of MNU, the animals were sacrificed and both eyes were enucleated immediatel...