[The role of isoprenoid chain of alpha-tocopherol in the protection of synaptosomes against lipid peroxidation and phospholipase A2-induced damage].

The role of the alpha-tocopherol molecule isoprenoid chain in synaptosomal membrane protection from lipid peroxidation activation and phospholipase A2 damage was investigated. A comparative study of alpha-tocopherol analogs differing in the length of the isoprenoid chain revealed that the increase in the chain length results in a decrease of the efficiency of inhibition in the course of synaptosomal lipid peroxidation activation. This effect is due to the diminution of mobility of chromanols in the lipid bilayer which is associated with an increase in the length of the isoprenoid fragment. The decreased efficiency of lipid peroxidation inhibition resulting from the lengthening of the chromanol nucleus phytol chain is concomitant with the appearance of new stabilizing properties, e. g., the ability to protect synaptosomal membranes from the damaging action of phospholipase A2. This effect is lost with a decrease in the length of the chromanol isoprenoid chain.