THE DEVELOPMENT OF HYPERTENSIVE NEURORETINOPATHY MODEL

Introduction: It should be noted the relevance of developing an adequate model of hypertensive neuroretinopathy for further study of neuroretinoprotective properties of pharmacological agents. Research tasks: Development of the methodical approaches for evaluation of the neuroretino protective activity of pharmacological agents to objectively assess the degree of the protective activity of new and commonly used neuroretinoprotectors in ophalmology. Methods: To investigate the fundus of experimental animals a direct ophthalmoscopy was used on 29th day of the experiment. The eye drops Irifrin 2.5% were used to expand the pupil. To zoom a lens Osher MaxField 78D model OI-78M has been used. Electroretinography was performed at once after the ophthalmoscopy. To assess the degree of functional damage to the retina we evaluated the ratio of amplitudes of a- and b- waves - the coefficient b/a. For all data, the descriptive statistics were used, and data are checked for normal distribution. Distribution type was determined by using the criterion of Shapiro-Wilk. Betweengroup differences were analyzed by parametric (t-Student criterion) or non-parametric (Mann-Whitney test) methods, depending on the type of distribution. Differences were determined at 0.05 significance level. Results: The results of ophthalmoscopy have found that the optimal model of pathology was with single 5-minute intraocular pressure (IOP) increase to 110 mmHg on day 26 of the experiment on the background of daily intraperitoneal N-nitro-L-arginine methyl ester (L-NAME) administration in a dose 12.5 mg/kg within 28 days: «Optic disc is edematous, increased in size, edema extends to the retina. Slight blurring boundaries of optic disc. There are pockets of "cotton" exudate, indicating the growing ischemia. Veins are congested, crimped at the periphery. Arteries are narrowed. Vessel caliber is uneven. Retina is palely (ischemic). Symptom Salus-Hun I. In rare cases, the solid exudate deposits were observed». In this group ratio b/a was 1.9 ± 0.08 r.u. (p<0.05 compared with the group of intact animals), which is less than the value of intact animals by 27%. Conclusion: The study developed a model of hypertensive neuroretinopathy on rats of Wistar line, ophthalmoscopic picture and retinal electrophysiological status were assessed that allows to fully appreciate the formation of the changes in the modeling of pathology. This model makes possible to evaluate the retinotropic effects of pharmacological agents sufficiently objectively. Key words: hypertensive neuroretinopathy, ophthalmoscopy, electroretinography.