The Effect Of Open Wounds Of Eyeball With Hypotony On The Rabbit Retinal Cell

Open wounds of eyeball often occur in clinics and result in vision decrease even lost. It usually destroy the integrality of eyeball, cause hypotony, inflammation, trauma cataract, proliferative vitroretinopathy, atrophy and other problems .Clinical observations have found the duration of eyeball with hypotony is connected with the extent of damage. Prolonged hypotony lead to irreversible change.We establish the animal model on open wound of eyeball with hypotony and examine ERG in different time, observe the apoptosis in the retina, provide the theoretical basis for clinical treatment.Meterial and methodForty New Zealand adult albinno rabbits were randomized into A, B, C, D and E groups(8 in each group, respectively),A as the control group. B, C, D, E as the experimental groups. Both of eyes in all animals were used as the study and examined before experiment, at 3 hour, 6hour, 12hour, 24 hour after trauma respectively.Morphological changes of the retinal were observed with light and electron microscopes. Functional changes were investigated by electroetinogram. The TUNEL (terminal deoxynucleotidyl-transferase mediated dutp end nick labelling) staining was used to identify retinal apoptotic cells .All the data were expressed by x s, analysed statisty by one-way analysis of variants, =0.05 as the standard.Result1. ERG indicated:The amplitudes of a, b waves declined and the latency prolonged in all the experimental groups. At 3 hour after trauma, no significant changes were found in both a and b-wave amplitude and latency(p>0.05). At 6 hour after trauma, the amplitude of b-wave show significant reduced (p<0.05).At 12 hour after trauma, the lesion of the retina is accelerared, both of a and b-wave show statistically significant changes(p<0.05). At 24 hour after trauma, obvious significant changes were found in both a , b-wave amplitude and latency, all the changes accord to the morphological changes of retina.2.HE staining indicated:Inner nuclear layer became disorder at 3 hour after trauma. Retinal ganglion cell and inner nuclear layer became nucleus shrunk, membrance intact, chromatin became packed against nuclear membrance at 6 hour after trauma. Retinal ganglion cell, inner nuclear and outer nuclear layer decrease in the number, disappear and disorder at 12 hour after trauma, retinal ganglion cell and inner nuclear lost and degeyative gradually. At 24 hour all the changes above even more distinguished.3.Electronmicroscopy examination indicated:the changes of ultrastructure are ealier than that of structure. In the experiment groups, all the layers of retina undergone pathological changes. The retinal ganglion cell became degenerated at first, and inner nuclear, outer nuclear layer became degenerated successively. The retinal pigment epithelium (PRE) undergone pathological changes at last. All the changes became more obvious with the ocular hypotony prolonged. The injury of retina with hypotony is progressive, persistant and degerative course.4.TUNEL indicate:No positive cells were observed in the normal retina and 3 hours after trauma. Cell with a positive reation for DNA fragmentation were observed as early as when it was at the 6 hour, reached a peak at the 12 hour and then decreased at the 24 hour.Conclusion1.We found pathology changes of retina after 3-6 hour. With the prolonged time, the pathological changes of the retina were more obvious.2.We should suture the wound as early as possible. Restoration the intraocular pressure and avoid the secondary damage to retina.