Changes in the parameters of pro-oxidant–antioxidant balance in the brain of rats with stepwise incomplete cerebral ischemia

Abstract

Objective: to evaluate the activity of oxidative stress in rats with stepwise incomplete cerebral ischemia (SICI). Material and methods. Experiments were performed on 24 male outbred rats weighing 260±20 g, allocated into 3 subgroups (6 animals in each) based on time of ligation of both common carotid arteries (CCA). The control group comprised of sham-operated rats of the same sex and similar weights (n=6). To identify the pro-oxidant–antioxidant state of the brain based on its homogenates, the activity of lipid peroxidation processes, the content of thiobarbituric acid reactive substances (TBARS), the concentration of reduced glutathione (GSH), total thiol groups (TSH), and the activity of glutathione peroxidase were determined. Results. SICI with ligation interval of both CCAs of 1 day and 3 days led to a significant decrease in the total SH groups of proteins and glutathione by 30% (p=0.038) and 46% (p=0.044), respectively, TBARS concentration by 29% (p=0.038) and 31% (p=0.043), respectively. SICI with the maximum interval between CCA ligations was manifested by less pronounced changes in the pro-oxidant–antioxidant state of the brain. Conclusion. In SICI with ligation of both CCAs 7 days apart, at which histological changes were the least pronounced, changes in the pro-oxidant–antioxidant balance were insignificant. The most pronounced disorders of the pro-oxidant–antioxidant balance in the brain were observed in the subgroup with the minimum interval between CCA ligations, which implied the highest activity of oxidative stress.