急性大鼠眼高压诱导的不同缺血/再灌内层视网膜的变化

目的：探讨急性眼高压诱导的不同缺血／再灌条件下内层视网膜形态与功能的变化。方法：成年大鼠，根据不同加压与再灌时间分组。左眼眼压升高至闪光视网膜电图b波消失的临界眼压且维持缺血30～90min。实验动物分别再灌1、3、7或14d复测b波，尼氏染色检测节细胞(RGCs)密度、内层视网膜厚度。结果：缺血60或90min组RGCs密度和内层视网膜厚度显著下降，且下降的程度随再灌时间的延长而加重。缺血30或45min组复测b波部分恢复；而缺血60min或更长时间组则b波未恢复。结论：缺血60min或更长时间导致内层视网膜严重损伤，而不同的眼高压维持时间和再灌时间都是影响视网膜损伤程度的重要因素。

Changes of inner retina under different ischemic reperfusion induced by acute intraocular hypertension in rats

Objective: To investigate changes of i nner retina in rat under different ischemic reperfusion conditions induced by acute intraocular hypertension. Methods: Adult SD rats were divided into groups according to the period of ischemic reperfusion. The intraocular pressure (IOP) of left eye was increased to make b wave of flash electroretinogragh (fERG) disappear and maintain for 30-90 min. 1, 3, 7 or 14 days later, fERG was recorded and density of retinal ganglion cells (RGCs) and thickness of inner retina were detected through Nissl staining. Results: Ischemia of 60 or 90 min resulted in significant decreases in the density of RGCs and thickness of inner retina. Simultaneously, severity of injury was depended on the reperfusion interval. B wave was recovered partly in the 30 or 45 min ischemic groups while not recovered in the 60 min or longer groups. Conclusion: Pressure-induced ischemia for 60 min or longer may lead to severe injury of the inner retina. Both the duration of the transient period of ischemia and the duration of reperfusion period influence injury extent of the inner retina.