Electron Microscopic and Immunohistochemical Examination of the Effect of 2-Aminoethoxydiphenyl Borate on Optic Nerve Injury in a Rat Model

Abstract

Objective: We conducted this study to explore the possible protective effect of 2-aminoethoxydiphenylborate (2-APB) on experimentally induced optic nerve injury in an acute ischemia-reperfusion (AIR) model.Materials and Methods: A total of 30 Wistar albino rats were randomly divided into sham, AIR, andAIR+treatment (AIR10) groups. In the sham group, AIR model was not created. In the AIR group, AIRmodel was created without the administration of drug. In the AIR10 group, 2-APB was administered 10 minbefore reperfusion.Results: Tissue samples were subjected to histological, immunohistochemical, and electron microscopic procedures. Histopathological examination revealed intense hypertrophic cells, more glial cells, capillary dilatation, and intense demyelination areas in the AIR group compared to those in the sham and AIR10 groups.Immunohistochemical staining demonstrated an increase in Orai1 and STIM1 immunoreactivity in the AIRgroup but less intense staining in the AIR10 group. Electron microscopy revealed injury in optic nerve axonsin the AIR group, whereas this type of injury occurred to a lesser extent in the AIR10 group.Conclusion: In rats, store-operated Ca2+ entry in the cell had an essential role in optic nerve ischemiareperfusion injury, and 2-ABP may have a protective effect on optic nerve injury caused due to AIR.