Currently, nitric oxide (NO) is considered a signaling molecule that acts as a universal regulator of many physiological processes in the body. The purpose of this research was to study the effects of exogenous NO on microcirculatory vessels and their blood flow under experimental conditions for the pathogenetic justification of NO therapy and correction of microcirculatory disorders. Methods. Effects of exogenic NO on microvessels of cranial pia mater were studied in white Wistar rats. Another set of experiments was carried out in hamsters to correct microcirculatory disorders caused by inflammatory-destructive lesions of the oral mucosa of the cheek pouch with NO therapy. Results. The effectiveness of the complex treatment of inflammatory-destructive diseases of the oral mucosa has increased with the use of NO. Conclusion. It has been established that the key factor in the positive effect of exogenous NO in therapeutic doses on blood microcirculation is the activation of vasomotor activity of microvessels. © Kozlov V.I. et al., 2024.