组织型纤溶酶原激活物诱发玻璃体后脱离的实验研究

目的研究玻璃体内注射组织型纤溶酶原激活物(tPA)诱发玻璃体后脱离(posteriorvitreousdetachment,PVD)的效果及安全性。方法12只灰兔分为实验A、B、C3组,每组4只,正常对照组1只。tPA10U,15U,25U(0.1mL),分别注入实验A、B、C3组兔的左眼作为实验组,0.1mLBSS分别注入右眼作为实验对照组。实验后分别观察0.5h、1h、2h、1d、7d的情况。扫描电镜、眼底检查、超声波用于PVD观察,透射电镜和视网膜电图用于药物安全性判断。采用SPSS10.0进行统计学分析。结果眼底和超声波检查发现实验A、B、C3组PVD发生率分别为25%、50%、100%,实验组总PVD发生率为58.3%,对照组无PVD发生,差异有高度显著性(P=0.002)。扫描和透射电镜显示实验C组发生完全性PVD,A和B组内界膜表面有玻璃体胶原残留。透射电镜和光镜检查发现各实验组的视网膜组织细胞未见异常,用药前后的视网膜电图差异没有显著性(P>0.05)。结论tPA能诱发人工PVD,25U在兔眼能安全和有效地诱发完全性PVD。

Efficacy and safety of t-PA in inducing experimental posterior vitreous detachment

Objective To investigate the effiency and safety of tissue-type plasminogen activator(t-PA)in inducing posterior vitreous detachment(PVD)in the rabbit eye.Methods Twelve pigmented rabbits were randomly divided into 3 groups (group A,B,C )that respectively received 10 U,15 U,25 U(0.1 mL)t-PA in left eye.The right eyes were injected with 0.1 mL BSS as control.0.5 hours,1 hour,2 hours,1 day and 7 days after operation,PVD was evaluated by biomicroscopy,ultrasonography respectively,scanning electron microscopy.Safety was evaluated by transmission electron,light microscopy and electroretinogram.Results In group A,B,C,incidence of PVD was 25%,50%,100% respectively under biomicroscopy and ultrasonography.In experimental group,total incidence of PVD was 58.3%.PVD didn't occur in control group(P=0.002).Complete PVD was observed in the group C that received 25 U t-PA under the scanning and transmission electron microscopy.Collagen fiber staining on the inner limiting membrane was observed in group A and B.In all experimental groups,safety was proved by the direct observation,microscopy and electroretinogram examination(P>0.05).Conclusion Intravitreal injection of t-PA at dose of 25 U can safely induce complete PVD in rabbits.