兔巩膜穿通伤后眼内细胞增生的放射自显影研究

目的　探讨巩膜穿通伤后巩膜伤口及其他眼内细胞的增殖过程。方法　通过巩膜穿刺及玻璃体腔注射自体血的方法制成兔眼巩膜穿通伤模型。在伤后不同时间处死动物。在处死前 2h向动物玻璃体腔注射3 H 胸腺嘧啶核苷 (3 H TdR)。眼球摘除后制成光镜、电镜标本及放射自显影标本 ,并对伤后不同时间巩膜伤口整合3 H TdR的细胞数进行比较。结果　眼球穿通伤后 ,炎症反应主要发生在浅层巩膜 ,巩膜伤口增生的纤维母细胞也主要来自浅层巩膜。增生的纤维母细胞沿嵌塞于伤口内的玻璃体纤维向玻璃体内血块的方向生长。增生的纤维条索牵引视网膜髓线、视盘 ,形成牵拉性视网膜脱离 (9/ 12 )。整合3 H TdR的细胞主要是伤口内的纤维母细胞。伤后 5天时整合3 H TdR的纤维母细胞最多(P <0 0 0 1) ,14天时显著下降 ,2 8天时几乎没有整合3 H TdR的细胞。放射自显影结果与光镜组织病理学结果一致。结论　巩膜穿通伤后炎症和增殖反应主要来自浅层巩膜 ,5～7天时细胞增殖性反应最为强烈。

An autoradiographic study of cell proliferatoin in penetrating wounds of sclera in rabbits

Objective To study the healing process of penetrating injury of sclera. Methods A rabbit model with penetrating injury of sclera was made by incising the sclera accompanied by intravitreous injection of autologous blood. The animals were sacrificed at different time intervals after injury. Two hours before the animals were sacrificed, 3 H thymidine ( 3 H-TdR ) was injected into the vitreous cavity. The enucleated eye balls were fixed, dehydrated, embedded with paraffin, and sectioned for light microscopic examination and autoradiographic study. The numbers of cells that incorporated 3 H-TdR at different time intervals were compared. Results After the sclera was injured, inflammation occurred mainly in the superficial part of the sclera, from which most of the proliferating cells filling the wounds came. These cells grew along the vitreous strands to the blood clot in the vitreous cavity. Tractional retinal detachments were induced in 9 of the 12 rabbits within 2 weeks after injury. Cells of different ocular tissues incorporated 3 H-TdR, of which the cells from superficial sclera accounted for the majority. Incorporation of 3H-TdR by these fibroblasts peaked on the 5th day after injury(P<0.001). By the 14th day, 3 H-TdR incorporation decreased abruptly, and 3 H-TdR positive cells were hardly found by the 28th day after injury. Conclusions Cells in sclera wounds proliferate most actively from the 5th to 7th day after injury. The majority of the proliferating cells come from the superficial sclera where inflammation is more profound.