Correlated changes and value of redox-status, nitric oxide and blood supply in experimental malignant tumor growth

With the use of methods of electronic paramagnetic resonance (EPR) and polarography EPR specter of tumor tissue, content of free nitric oxide and intensity of local hemo circulation in dynamics of sarcoma S-45 growth has been studied. It was stated that the intensity of local hemo circulation (especially in center of tumor tissue) progressively decreases. Sharp decrease of hemo circulation in the central part of the tumor tissue could be explained by drastically reduced concentration of NO, which in turn is related to disorders in electron transport in mitochondrial respiratory chain and probably to conversion of NO into toxic peroxinitrite. The relatively less expressed decrease of local hemo circulation in periphery, despite impaired reheological features of the blood, is explained by increased concentration of NO. It is suggest, that tumor tissue blood supply enhancement increases chemotherapeutic effects via affecting energetic metabolism in mitochondria, redox-status and concentration of free NO.