Anderson R E, Maude M B, Nielsen J C
Curr Eye Res. 1985 Jan;4(1):65-71. doi: 10.3109/02713688508999969.
We have developed an in vitro system in which lipid peroxidation can be produced in a predictable fashion and have studied the effects of peroxidation on regenerability of rhodopsin in rod outer segments (ROS). ROS isolated by sucrose flotation from dark-adapted retinas of Rana pipiens were suspended in various concentrations of FeSO4 and 1 or 2 mM ascorbic acid for 10 minutes. An increase in lipid hydroperoxides (measured as conjugated dienes) and a decrease in 22:6 omega 3 were determined for each Fe+2 concentration and used as an index of peroxidation. Following incubation with and without FeSO4, ROS were pelleted and rhodopsin was regenerated with 15 micron 11-cis-retinal. The regenerability of rhodopsin in ROS in which significant lipid peroxidation had taken place was reduced by 40-50% compared to controls. DTPA (diethylenetriamine pentaacetic acid), EDTA, and EGTA protected against lipid peroxidation by Fe+2 and allowed almost complete regeneration of rhodopsin. Incubation with DTPA also prevented the destruction of vitamin E in ROS. Other compounds containing primary amine groups did not protect against peroxidation or loss of regenerability. These experiments indicate that lipid peroxidation is associated with a loss of regenerability of the visual pigment rhodopsin.
我们开发了一种体外系统，在该系统中可以以可预测的方式产生脂质过氧化反应，并研究了过氧化反应对视杆细胞外段（ROS）中视紫红质再生能力的影响。从暗适应的牛蛙视网膜中通过蔗糖浮选法分离得到的ROS悬浮于不同浓度的硫酸亚铁和1或2 mM抗坏血酸中10分钟。测定每个亚铁离子浓度下脂质氢过氧化物（以共轭二烯衡量）的增加以及22:6 ω-3的减少，并将其用作过氧化反应的指标。在有和没有硫酸亚铁的情况下孵育后，将ROS沉淀，并用15微米的11-顺式视黄醛使视紫红质再生。与对照组相比，发生显著脂质过氧化反应的ROS中视紫红质的再生能力降低了40-50%。二乙三胺五乙酸（DTPA）、乙二胺四乙酸（EDTA）和乙二醇双四乙酸（EGTA）可防止亚铁离子引发的脂质过氧化反应，并使视紫红质几乎完全再生。用DTPA孵育还可防止ROS中维生素E的破坏。其他含有伯胺基团的化合物不能防止过氧化反应或再生能力的丧失。这些实验表明脂质过氧化反应与视觉色素视紫红质再生能力的丧失有关。
