PATHOMORPHOLOGICAL CHANGES IN THE RETINAL LAYERS AT THE END OF THE SEVENTH DAY OF EXPERIMENTAL OPIOID EXPOSURE

Abstract

The aim of the work was to clarify the fundamental issues regarding the dynamics of early changes in the retinal layers under experimental exposure of opioids. Research was done on 15 adult 4-months-old mature male mongrel rats, having 100.0-160.0 g weight. Opioid eff ects were modelled by daily intramuscular injections of nalbuphine 1 time per day in one period of time (10-11 am) for 7 days. The initial dose of nalbuphine was 0.212 mg ̸kg. Histological slides were prepared according to generally accepted methods using the dyes, as hematoxylin, eosin and azan according to the Heidenhain method.All animals were kept in the vivarium and the work was carried out according to the European Convention for t he Protection of Vertebrate Animals used for experimental and other scientifi c purposes [Strasbourg, 1985]. During the experimental opioid administration after one week of research the changes in the structure of the retinal layers were established. In the early stages of low-dose opioid analgesia administration, the fi rst pathomorphological changes were de tected during the fi rst week, in the form of initial manifestations of vacuole dystrophy of the pigmental epithelium, signs of microcystic degeneration of the outer retinal and neurofi brous layers with the vacuole dystrophy of retinal ganglion cells appearance.