Objective: In order to search for simple and effective medicine to protect light-induced retinopathy.
Method: We used verapamil as a protective agent. We measured the contents of the end product of lipid peroxidation, malondialdehyde (MDA), in the rat retinas immediately, 4 days, 15 days and 30 days after the damage in the damaged group and protective group, and observed their histopathologic structures and the integrity of the outer blood-retinal barrier.
Results: The results showed that the content of MDA in the normal retina was 0.36 +/- 0.07 nmol/mg, while in the damaged group the MDA levels at different times were 0.52 +/- 0.03 nmol/mg, 0.70 +/- 0.20 nmol/mg, 0.52+/- 0.07 nmol/mg, and 0.47 +/- 0.03 nmol/mg respectively, being significantly different from that of the normal group. In the protective group, the MDA levels at different times were 0.40 +/- 0.04 nmol/mg, 0.49 +/- 0.03 nmol/mg, 0.40 +/- 0.05 nmol/mg and 0.39 +/- 0.08 nmol/mg respectively, being significantly different from that in the damaged group at the corresponding times. In the damaged group, the histologic study showed that the retinal structures were damaged in various degrees at 4 days and most severely at 15 days after light exposure and the outer blood-retinal barrier was also damaged, while in the protective group no significant pathologic changes of retina were seen.
Conclusion: Verapamil is an effective protective medicine for light-induced retinopathy.