Pharmacological correction of retinal ischemia/reperfusion by minoxidil

Abstract

Introduction/Objective. The objective of this paper was to increase the effectiveness of pharmacological correction of retinal ischemia-reperfusion by using minoxidil. Methods. The research was carried out on 180 Wistar rats. A modification of the retinal ischemia-reperfusion model was used, in which an increase in intraocular pressure is carried out by mechanical pressure (110 mmHg) to the front chamber of the eye for 30 minutes. Protective effects of minoxidil at a dose 0.5 mg/kg on the model of retinal ischemia-reperfusion were estimated by the changes in the level of retinal microcirculation (laser Doppler flowmetry), electroretinogram amplitude, morphometry of retinal layers after 1 hour and 72 hours of reperfusion. Results. Minoxidil at a dose 0.5 mg/kg of rat mass improves retinal microcirculation, its electrophysiological state after 1 hour and 72 hours of reperfusion, and prevents the development of degenerative changes in the retina caused by ischemic damage to a greater extent than recombinant erythropoietin at a dose of 50 IU/kg and sildenafil at a dose of 0.5 mg/kg in monotherapy. The protective effects of minoxidil were eliminated by the preliminary administration of glibenclamide at a dose of 5 mg/kg, which indicates the presence of the preconditioning effect of minoxidil, realized through adenosine triphosphate-dependent potassium channels. Conclusion. Minoxidil at a dose of 0.5 mg/kg of rat mass protects the retina from ischemic-reperfusion injury. Protective effects of minoxidil are carried out by a preconditioning action, as evidenced by the lack of positive effects with the administration of glibenclamide.

Keywords

• ischemia-reperfusion
• retina
• minoxidil
• erythropoietin
• sildenafil
• ATP-dependent potassium channels