Doly M, Braquet P, Droy M T, Bonhomme B, Vennat J C
J Fr Ophtalmol. 1985;8(3):273-7.
Particularly rich in polyunsaturated fatty acids, the retina constitutes an excellent model for testing the functional consequences of membrane lipoperoxidation. The effects could be quantified by measuring the amplitude of the electroretinogram which represents the characteristic response of the retina to its physiological stimulus (light photons). The authors report results obtained on isolated rat retina maintained in survival by perfusion. The membrane lipid peroxidation is induced by the non enzymatic catalytic system (Fe2+ + ascorbate). In the presence of such a system, the amplitude of the b-wave of the electroretinogram rapidly decreases and the survival time is notably shortened. These results are discussed with regards to the mechanism generating the electroretinogram and the specific role played by the disk membrane and plasmic membrane of the rod outer segment. Finally, the authors test the radical scavenger properties of a Ginkgo biloba extract. The results indicate that such an extract develops an antiperoxidative effect probably connected with its flavonoid composition. With this extract the survival time of the isolated retina is significantly increased and this result could be related to the retinal cell membrane disorders observed in diabetes.
视网膜富含多不饱和脂肪酸，是测试膜脂过氧化功能后果的极佳模型。通过测量视网膜电图的振幅可以量化这些影响，视网膜电图代表视网膜对其生理刺激（光量子）的特征反应。作者报告了在通过灌注维持存活的离体大鼠视网膜上获得的结果。膜脂质过氧化由非酶催化系统（Fe2+ + 抗坏血酸）诱导。在这种系统存在的情况下，视网膜电图的b波振幅迅速降低，存活时间显著缩短。结合产生视网膜电图的机制以及视杆外段的盘膜和质膜所起的特定作用对这些结果进行了讨论。最后，作者测试了银杏叶提取物的自由基清除特性。结果表明，这种提取物具有抗过氧化作用，可能与其黄酮类成分有关。使用这种提取物，离体视网膜的存活时间显著延长，这一结果可能与糖尿病中观察到的视网膜细胞膜紊乱有关。
