Vinpocetine protects inner retinal neurons with functional NMDA glutamate receptors against retinal ischemia. (February 2018)

• Record Type: Journal Article
• Authors: Nivison-Smith, Lisa; Khoo, Pauline; Acosta, Monica L.; Kalloniatis, Michael
• Is Part Of: Experimental eye research. Volume 167(2018)
• Page Start: 1
• Page End: 13
• Publication Date: 2018-02
• Subjects: Vinpocetine -- Retinal ischemia -- NMDA glutamate receptors; Ophthalmology -- Periodicals; Eye -- Periodicals; Œil -- Périodiques; Ophthalmology; Periodicals; Electronic journals; 612.8405
• DOI: 10.1016/j.exer.2017.10.008
• Languages: English
• ISSNs: 0014-4835

Abstract

Abstract: Retinal ischemia is involved in the pathogenesis of many major vision threatening diseases. Vinpocetine is a natural drug, which has a range of neuroprotective actions against retinal ischemia including modulating cation flow, improving metabolic activity and preventing apoptosis. The exact mechanism behind these actions remains unknown but may involve glutamate receptors, major components of the ischemic cascade. This study examined the effects of vinpocetine in association with specific ionotropic glutamate receptor agonists: N-methyl-D-aspartate (NMDA) and kainate. Vinpocetine's actions to improve cation channel permeability and cell marker immunoreactivity following ischemia appeared to be limited to NMDA activation with no changes observed following kainate stimulation. Vinpocetine's actions were lost in the presence of an NMDA receptor inhibitor further suggesting they may be secondary to NMDA receptor activation. NMDA receptor function was also necessary for vinpocetine's actions on glucose availability during ischemia but not lactate dehydrogenase (LDH) activity in the ischemic retina suggesting not all of vinpocetine's actions are linked to NMDA receptor function. These results may explain vinpocetine's effectiveness as a neuroprotective agent as the NMDA receptor is implicated in the pathogenesis of ischemia in a range of tissues of the central nervous system. Highlights: Vinpocetine's actions in retinal ischemia are limited to neurons with NMDA receptors. Vinpocetine's actions were not observed for neurons with kainate receptors. Vinpocetine's actions on glucose were also linked to NMDA receptor function. Some of vinpocetine's actions in ischemia are secondary to NMDA receptor function.