兔眼玻璃体腔内注射纤维蛋白溶酶和透明质酸酶诱导形成玻璃体后脱离

Posterior vitreous detachment induced by in-travitreal injection of plasmin combined with hyaluronidase in the rabbit

目的考察2种酶类药物纤维蛋白溶酶(plasmin,P)和透明质酸酶(hyaluronidase,HS)兔眼内联合应用诱导形成玻璃体后脱离(posteriorvitreousdetachment,PVD)的作用。方法取新西兰大白兔20只,将HS与P各0.5U联合应用,注入20只右眼玻璃体腔内,左眼内各注入等量生理盐水作为对照。在设定的时间点(15min-7d),通过活体的直、间接眼底镜、视网膜电图(ERG)检查和摘除眼球的光、电镜检查,从形态学方面对酶作用于玻璃体的效应及其眼部毒性进行观测。结果在实验观察期内:(1)实验眼从第3d开始有肉眼可见的PVD形成;(2)实验组注药前后各时间点ERGb波振幅比值分别为(0.899±0.112)、(0.968±0.112)、(0.997±0.149)、(0.934±0.114)、(1.056±0.164):对照组分别为(0.961±0.074)、(0.983±0.145)、(0.962±0.056)、(0.963±0.112)、(1.040±0.094);2组比值没有明显差异(P>0.05);(3)光、电镜下视网膜的各层结构在玻璃体注射后无明显改变。结论玻璃体腔内联合注射0.5UP酶和HS酶可有效地诱导产生PVD,而且对视网膜的结构和功能无毒性损害。

Objective To study the effect of pharmacologic Induction of posterior vitreous detachment(PVD)by intravitreal injection of plasmin(P)together with hyaluronidase(HS). Methods 0.5 U of P combined with 0.5 U of HS were injected into the vitreous cavity of twenty right eyes of New Zealand white rabbits. The left eyes,intravitreally injected by the same volume of NS, were considered as control. Observation period was from 15 minutes to 7 days. Ophthalmoscopy, electroretinography (ERG) and histological examination were performed to assay morphologically the enzymes' s effectiveness to produce PVD and their probable toxicity to the retina. Results During the observation period: (1) clinical PVD found by naked eye could be successfully induced in the right eyes on the third postinjection day; (2) the ratio of bA of post-injection to pre-injection in experiment group were(0.899 ± 0.112), (0.968 ±0.222), (0. 997±0.149), (0. 934±0.114), (1. 056 ±0.164); control group were (0.961±0.074) ,(0.983±0.145), (0.962±0.056),(0.963±0.112), (1.040±0.094); no statictic difference were found between the two groups; (3)histological examination showed normal structure of the retina in the treated eyes. Conclusion The combination of two enzymes,P and HS,can induce PVD successfully, and is safe to the retina's structure and function of the rabbit eyes.