糖尿病大鼠药物性玻璃体松解术的研究

摘要

目的 研究在糖尿病大鼠中能否采用药物性玻璃体松解术诱导完全性玻璃体后脱离(PVD).方法 实验研究.成年SD大鼠用链脲佐菌素(STZ)腹腔注射诱发糖尿病,4周后用视觉电生理、视网膜血管铺片、透射电镜观明确视网膜病变的发生.发病4周后将糖尿病大鼠分为4组:A组10只,右眼玻璃体内注射透明质酸酶5 U;B组10只,右眼玻璃体腔内注射纤溶酶0.5 U;C组10只,右眼玻璃体腔内注射纤溶酶0.5 U+透明质酸酶5 U;D组10只,右眼玻璃体注射BSS 2 μl.注射后一周内观察眼部一般情况并检查视觉电生理变化(F-ERG).一周时取各组大鼠视网膜做扫描电镜检查和组织切片,观察视网膜组织结构及玻璃体后脱离的发生情况.对数据采用t检验进行统计学分析.结果 糖尿病大鼠发病4周时已经有视觉电生理的改变,血管铺片显示周细胞的减少(t=6.1,P<0.01);Ops振幅降低、峰时延迟(t=2.8,3.4;P<0.05);透射电镜显示毛细血管周细胞水肿变性.玻璃体腔注射药物一周后,通过扫描电镜观察A组和D组无PVD发生(0/10);B组发生部分性PVD 6/10,完全性PVD 4/10;C组发生完全性PVD 10/10.视觉电生理检查各组与注射前相比差异均无统计学意义(P>0.05),组织切片检查未显示视网膜组织结构的异常改变.结论 STZ诱导糖尿病4周大鼠视网膜已经出现了病理改变,在其玻璃体腔中注射0.5 U的纤溶酶加5 U的透明质酸酶能够稳定地诱发出完全性PVD,而单独使用纤溶酶仅能诱发出部分性PVD,透明质酸酶不能诱发出PVD.各组未见药物对视网膜的结构和功能造成明显的毒性反应.%Objective To evaluate the efficacy and safety of plasmin or hyaluronidase in the inducing of posterior vitreous detachment in diabetic rats. Methods Forty SD rats were induced diabetes by Streptozotocin (STZ). Four weeks later, these rats were randomized into 4 groups : rats in group A received 5 U hyaluronidase intravitral injection in right eyes;rats in group B received 0. 5 U plsmin intravitral injection in right eyes;rats in group C received 0. 5 U plasmin + 5 U hyaluroniclase intravitral injection in right eyes;rats in group D received BSS (balance salt solution ) 2 μl intravitral injection in right eyes. Clinical examination were performed at 1, 3, 7 days after injection. After 1 week, scanning electron microscope (SEM) was performed to judge whether the PVD was induced. ERG and histology were examined to evaluate the toxicity after the intravitreal injection of these two drugs. Results No PVD was found in SEM disclosed group A and group D. Forty percent eyes were induced complete PVD in groups B, and one hundred percent eyes were induced complete PVD in group C. ERG and histology showed no toxicity changes in any group. Conclusion Intravitreal injection of 0. 5 U plasmin + 5 U hayluronidase can induce complete PVD without obvious toxicity in diabetic rats. Solo usage of plasmin or hayluronidase can not induce complete PVD.