SOURCES OF SUPEROXIDE ANION RADICAL IN SMALL INTESTINE TISSUES IN RATS SUBJECTED TO SURGICAL TRAUMA SIMULATED UNDER EXPERIMENTAL MODEL OF POSTTRAUMATIC STRESS DISORDER

The sources of superoxide anion radical (.О ) in the tissues of the small intestine in rats subjected to surgical trauma simulated under an experimental model of posttraumatic stress disorder (PTSD) were investigated. The study involved 42 white Wistar rats weighing 210-230 g, divided into 6 groups: group 1 comprised intact animals, group 2 included animals with the PTSD induced through single-prolonged stress (SPS), group 3 consisted of rats subjected to a sham surgical operation, group 4 comprised animals undergoing laparotomy, group 5 involved rats undergoing a sham surgical operation following SPS, and group 6 included animals undergoing laparotomy under modeled SPS. The rate of .О generation in the small intestine homogenate was measured spectrophotometrically using the nitroblue tetrazolium test. The .О production by NADPH-dependent (microsomal and NO synthase) electron transport chains (ETC), NADH-dependent (mitochondrial) ETC and leukocyte NADPH oxidase was assessed. The findings obtained have demonstrated that experimental SPS modeling leads to an increase in oxidative stress in the small intestine tissues of rats. This is manifested by an increase in the rate of .О formation with the participation of microsomes, mitochondria and leukocyte NADPH oxidase. On the 7th day after laparotomy under the experimental PTSD model, the .О production in the tissues of the small intestine by different sources (microsomes, mitochondria and leukocyte NADPH oxidase) exceeds their values obtained after a single laparotomy or after performing a sham operation under single long-term stress.