海水对兔眼视网膜形态学的影响

Effects of seawater on morphology in the retina of rabbits

目的观察海水进入兔眼玻璃体后不同时间视网膜组织的形态学改变。方法25只健康成年新西兰白兔按伤后30min、2h、6h、12h和24h随机均分为5组,以每组动物右眼为实验眼,左眼为自身对照眼。实验眼玻璃体中注射0.5ml实验用人工海水,对照眼注入0.5ml平衡盐溶液。分别在伤后30min、2h、6h、12h和24h用光学显微镜和透射电子显微镜观察视网膜的组织形态学变化。结果对照组兔眼视网膜组织结构层次清楚,染色均匀,细胞形态规整,未见明显病理改变。实验眼30min组视网膜神经节细胞层稍水肿,2h组神经纤维水肿明显,视网膜内节线粒体肿胀,空泡变性。6h时内核层细胞数开始减少,12h组视网膜神经节细胞层和内核层出现细胞核碎裂、边集,细胞数目明显减少。光感受器细胞内线粒体空泡变,核膜皱缩,内陷,内外节空泡变明显增多。结论海水进入兔眼玻璃体早期即可引起视网膜组织形态学发生改变,随着时间的延长,组织损伤逐渐加重。6～12h即发生不可逆性改变。

Objiective To observe the morphological changes of rabbitg retina at different time points at which seawater was injected into the vitreous of rabbits. Methods Twenty-five New-Zealand white rabbits were randomly assigned to five groups, as 30 minutes, 2 hours, 6 hours, 12 hours and 24 hours group following the seawater injection in the vitreous. The right eyeball served as experimental eyeball and the left one as control in each group. 0. 5ml artificial seawater was injected into the intermedius of rabbits right vitreous. 0.5ml balanced salt sdution was injected into the left vitreous in the same way. At different time points following the eyeball injury, the morphological changes of retina were observed with light microscope and transmission electron microscope. Results The retina of control eyeballs had clear layers and regular cell shape in retinal structures with conventional staining. For the experimental eyeballs, the ganglion cell layer began to swelling after 30 minutes of seawater injection. The nerve fiber swelled obviously and the mitochondria vesiculated and swelled in the inner segment at 2 hours of seawater injection. The cell population of the inner nuclear layer began to reduce in 6 hours. At 12 hours of seawater injection, the retinal damages included disorganized cell nuclei, decreased cell population in ganglion cells and inner nuclear layer. Mitochondria vesiculated in photoreceptor cells, nuclear membrane shrank and sank inward. The vesiculation on inner and outer segments increased obviously. Conclusions Seawater may cause the morphological changes of rabbits retina at early stage, and the histological damages become aggravation following the time prolongatio. The damages would be unrecoverable 6 to 12 hours after seawater injury.