[The role of nitric oxide in the development of humoral immune response in mice]

The immune response in CBA mice was evoked by injection of sheep erythrocytes. The number of antibody-producing cells in the spleen, as well as nitric oxide production, oxygen-dependent metabolism and 5"-nucleotidase activity of peritoneal macrophages and lymphocytes were studied on days 1-5-14 after immunization. It was shown that during the inductive phase of the immune response (day 1), the peritoneal cells increased nitric oxide production, while later their functional activity increased and NO level became normal. The use of NO-synthase inhibitors (non-selective L-NNA and iNOS inhibitors SMT and dexamethasone) increased the immune response and decreased the macrophage functional activity. The use of NO-donator SNP resulted in reverse effect: decrease of the immune response and stimulation of peritoneal cells functional activity. The data obtained indicate that nitric oxide participates in the immune response regulation, in particular, through the suppressive effect of macrophages.