TANE Nobuhiro School of Medicine, Shimane Medical University, Instractor, 医学部, 助手 (50277993)
OHIRA Akihiro School of Medicine, Shimane Medical University, Professor, 医学部, 教授 (00169054)
We used ocular hypertension model, such as retinal ischemia/reperfusion, by which retinal edema was performed in Sprague-Dawley line white rats. Retinal ischemia was made up by physiological saline perfusion with 150 cm H_2O pressure from 27 gauge needle which was stabbed into the anterior chamber. Retinal reperfusion was acquired stpping 150 cm H_2O pressure. Retinal ischemia/reperfusion was confirmed by ophthalmoscopic examination observing the disappearance and resumption of pulstion of retinal artery under mydriatic condition. Several groups were classified by the time after retinal ischemia/reperfusion, namely, 0 hour (immediately), one hour, 6 hours, 12 hours, 24 hours, 3days, 7 days, 14 days. Control group is not with loading stress. Enucleation was performed in each group. The retina of each group was investigated by immunohistochemical assay using monoclonal antibodies for aquaporin-1, 2.
2. Results and Conclusions
Aquaporin-1 expression was observed in the photorecepter inner segments of 12 hours group and the ganglion cell layer of 7 days group. No specific staining was detected in the other group.
Strong aquaporin-2 expression was detected in ranging the inner limiting membrane from the inner plexiform layer of 0 hour group. Aquaporin-2 expression was not observed in the other group.
Aquaporin-2 expression was observed immediately. Morphologically, aquaporin-2 expression cells are considered to be Muller cells.In early stage of retinal edema, it is probably that Muller cell act as the transporter of the interstitial fluid which is pumped out into the vitreous cavity. Considering slow aquaporin-1 expression, aquaporin-1 is probably to be related to the delayed reactions of retinal edema. If the drugs inducing aquaporins are developed in the future , these may be effective for retinal edema and useful for visual recovery.