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The attention of many researchers in fundamental and applied neurology is focused on the molecular mechanisms of pathogenesis of acute epileptoid seizures. The absence of principally new information, which would allow understanding the real cause-effect factors that determine the nature of this pathology, considerably hampers the search for measures on elimination and correction of causes underlying initiation, development, and generalization of ethiopathogenic mechanisms of epilepsy.In view of this, disorders occurring in different structures (both in whole cells and subcellular formations), as well as metabolic processes and functional activities characteristic of them, merit special attention. This primarily applies to the cell membranes that play a key role in dramatic disturbances of blood circulation in general and microcirculation in the brain in particular [1]. Ideas on metabolic disturbances in cell membranes occurring during epileptoid seizures are mostly focused on the major component of these formationsvarious phospholipids (PLs) of neutral and acid nature (NPLs and APLs, respectively), whose qualitative composition and content are constant, phylogenetically based characteristics [2]. For this reason, there is no doubt that phospholipids play a key role in the development of normal rhythm of metabolic transformations that ensure cell activity in general, as well as its structural, metabolic, physicochemical, and functional characteristics [3]. Disturbances in the latter are manifested especially distinctly against the background of toxic effects on the organism, which completely disturb normal stereotype of vital functions of the cell and its components [4-6].Taking into account the above-listed facts, in this study we sought to investigate how experimental epileptoid seizures induced by corazolum in white rats cause quantitative and qualitative disturbances in phospholipids, affect the proportion between phospholipids, and change the quotient K -the ratio between total neutral phospholipids (lysophosphatidylcholines, sphingomyelins, phosphatidylcholines, and phosphatidylethanolamines) and total acid phospholipids (monophosphoinositides, phosphatidylserines, and cardiolipins). We suggest that variations [7] in the quotient ä are sufficient to assess the metabolic and functional state of biological membranes (in particular, erythrocytic membranes) in one or another extremal or pathological condition of the organism. Another goal of this study was to search possible approaches for the most efficient antioxidant defense. For this purpose we selected vitamin E (the major component of the endogenous system of antiradical defense of the cell) and sodium thiosulfate (the most potent synergist of vitamin E), which distinctly exhibit antitoxic antistress properties.As a key factor in the regulation of activity of protein kinase C, vitamin E at ultralow concentrations (as low as 10 -15 M [8]) is apparently the main stage of implementation of the favorable effect of sodium thiosulfate in numerous malfunctions (i...

Currently, it is commonly believed that lipid peroxidation products are involved in the mechanisms regulating cell activity both in normally metabolizing and pathologically changed biological systems of organisms [1]. Free-radical lipid peroxidation is accompanied by a release of a significant amount of compounds exhibiting membranotoxic and membranotropic effects, which, according to current notion, may manifest themselves both as stimulation or inhibition of various metabolic processes at different stages of cell formations [2][3][4][5][6][7]. With regard for these facts, we strongly believe that intensification of lipid peroxidation processes is a necessary but not specific factor in a complex of pathogenic mechanisms of any pathological and extremal state of the organism [8][9][10]. It was reported that conjugated dienes function as allosteric effectors of various enzymes; their action obeys the principles of kinetic cooperativity [5,6] and cause changes in the viscosity of the lipid component of plasma membranes [11].Taking into account the aforementioned facts, the goal of this study was to investigate the characteristic features of the process of lipid peroxidation in the brain, liver, and whole blood of albino rats in epileptoid seizures induced by corazolum.The study was performed with 44 nonpurebred male albino rats weighing 180-200 g, which were kept under standard vivarium conditions. Rats received single intramuscular injections of corazolum(dose, 8-9 mg per animal), sodium thiosulfate (STS, 1 mg per animal), and vitamin E (0.4 mg per animal). When forming corazolum-induced seizures against the background of preliminarily injected STS and vitamin E, corazolum was injected 15 min after injecting these antioxidants.In the first series of experiments, we studied 19 rats that received single intramuscular injections of corazolum (dose, 8-9 mg per animal). In the second series of experiment, 25 rats received corazolum injections after preliminary injections of either 0.4 mg of oil solution of vitamin E (subseries 1) or 1 mg of STS per animal. These agents were injected 15 min before corazolum injections.Rats were decapitated under light ether anesthesia when they had pronounced epileptoid seizures. Whole blood preparations were stabilized with oxalate or citrate solutions at standard concentrations (ratio, 9 : 1). The brain and liver were immediately extracted in the cold, cleared from capsules and blood vessels, and homogenized. Homogenates were tested for lipid peroxidation products. The rate of free-radical lipid peroxidation in this biological material was assessed by the yield of malonic dialdehyde (MDA) according to the conventional procedure [12,13]. The amount of MDA was expressed in nmoles per mg protein; protein content was determined by the method of Lowry [14].In the first series of experiment, we studied the effect of the specified doses of vitamin E and STS separately on the rate of free-radical lipid peroxidation, which was assessed by the changes in the MDA content in the brain, liver, and...