Retina-Vitreous
2001 , Vol 9 , Num 2
PROTECTION OF THE GUINEA PIGS RETINA FROM ISCHEMIA-REPERFUSION INJURY BY MELATONIN
Fırat Ü.Tıp Fak.Göz Hast.A.D., Elazığ
Purpose: The purpose of this study is evaluating the protective effect of melatonin on retinal ischemia-reperfusion (I/R) injury in guinea pigs. Methods: Thirty male guinea pigs weighing 400-600 gr were divided into 3 groups with randomly selected. Group 1 (control group) was not applied any procedure, only to determine normal values, group 2 (I/R group) was applied ischemia-reperfusion and received serum physiologic as placebo, group 3 (melatonin group) was applied ischemi-reperfusion and received melatonin. Retinal ischemia was induced to group 2 and 3 by raising saline resorvoir to a height of 204 cm thereby increasing the intraocular pressure to 150 mmHg for 90 minutes. Ten minutes before the onset of ischemia, 1 ml serum physiologic injected subcutaneously to I/R group and 10 mg/kg melatonin injected subcutaneously to melatonin group. We repeated the same doses at 6th, 12th and 18th hours. After 90 minutes of ischemia intraocular pressure reduced to normal values and reperfusion was performed for 24 hours, then eyes were enucleated.
Results: In the I/R group vacuolization and edema in photoreceptor layer, degenerative changes and edema of the ganglion cells were significantly higher than melatonin and. control group at histopathologic evaluation (p<0.01 and p<0.001) Between the control and melatonin groups there was not any significant difference about vacuolization and edema in photoreceptor layer, degenerative changes and edema of the ganglion cells (p>0.05).
Conclusion: According to histopathologic evaluation in retinal I/R induced eyes, melatonin decreased and limited the cellular damage. Keywords : Melatonin, Ischemia-reperfusion, Retina