Application of EPR spectroscopy to study the content of NO and copper in the frontal lobes, hippocampus and liver of rats after brain ischemia

Abstract

Electron paramagnetic resonance (EPR) spectroscopy was used to record the content of nitric oxide (NO) and copper in brain tissues (frontal lobes and hippocampus) and liver of healthy rats and rats after ischemia modeling. Ischemia was simulated by ligation of the carotid arteries, followed by taking 3 ml of blood from the common carotid artery. Signals from triple complexes (DETC) were recorded by EPR spectroscopy of complexes (DETC)2-Fe2+-(NO) and Cu(DETC)2. Based on direct measurements by EPR spectroscopy, it was shown that a day after the modeling of ischemia, NO production in the hippocampus decreases by an average of 30% and there is a tendency to decrease NO in the frontal lobes and liver. The copper content decreased by an average of 3 times in the frontal lobes and the hippocampus by an average of 20% a day after ischemia modeling, and a tendency to decrease was noted in the liver. Thus, brain hypoxia is accompanied not only by a decrease in NO production, but also by signs of weakening of the antioxidant system in the hippocampus and frontal lobes, which further worsens the functional state of the homeostasis system. Keywords: electron paramagnetic resonance, spin trap, nitric oxide, cerebral ischemia, frontal lobes, hippocampus.