大鼠视网膜缺血后一氧化氮合酶阳性神经元的变化

VARIATION OF NITRIC OXIDE SYNTHASE POSITIVE NEURONS IN ISCHEMIC RETINA OF RAT

本文用前房加压灌注视网膜缺血模型、β－ＮＡＤＰＨ脱氢酶组化方法研究了ＳＤ大鼠视网膜内含一氧化氮合酶（ＮＯＳ）神经元的分布及其变化。实验动物依缺血时间分四组，分别为缺血１０ｍｉｎ、１５ｍｉｎ、３０ｍｉｎ及６０ｍｉｎ组。将ＮＯＳ阳性细胞进行计数统计，做自身配对ｔ检验及方差分析。实验结果表明正常及缺血视网膜ＮＯＳ阳性神经元。大多数位于内核层，少数位于节细胞层；ＮＯＳ阳性细胞在视网膜中央区密度高于周边区，而各象限的平均密度分布无明显差别。缺血１５ｍｉｎ后内核层的ＮＯＳ阳性细胞开始减少，随缺血时间的延长细胞减少更为明显。各组均以视网膜中央区变化较为显著，提示视网膜缺血１５ｍｉｎ后即可出现神经生物学变化，视网膜中央区对缺血比周围区更为敏感。

The distribution and variation of Nitric oxide synthase (NOS) positive neurons in the ischemic retina of the SD rats were studied with β NADPH diphorase histochemistry method. The experimental animals were divided into 4 groups according to different ischemic time namely 10, 15, 30 and 60 min. The NOS positive cells were counted and analysed. The result showed the distribution of NOS positive cells were the same either in normal or in ischemic retina. The somata of NOS positive neurons were located in the inner nuclear layer (INL) and the ganglion cells layer (GCL). The average density of NOS positive cells in central area is higher than that of peripheral area but there is no difference in each quadrant of retina. After 15 min of ischemic treatment the NOS positive cells decreased and become more clearly along with ischemic time prolonged. The variation was more obvious in central area than that of peripheral area. Our study indicated that the variation of neurobiology may occur in the retina after 15 min ischemia. The central area of the retina is more sensitivity than that of peripheral area.