Effects of Nitric Oxide Donors on the Biological Activity of Human Neutrophils in Vitro. Review Own Studies

This review summarizes our investigations on the reactivity of human polymorphonuclear neutrophils treated with the pharmacologically active compounds that liberate nitric oxide in vitro. The results of our study show that nitric oxide liberation from sodium nitroprusside (SNP), 3- morpholinosydnonimine (SIN-1) and Diethylamine/NO is a time-and dose-dependent and the kinetics of NO production is different between the three compounds. The effect of exogenously administered compounds on the neutrophil functional state depends on the compounds concentration, rate and mechanism of NO liberation, treatment time of neutrophils and on the stimulus employed to cells activation. SNP and DEA/NO actions on neutrophil respiratory burst are mainly associated with modulation of PKC and MEK1/2 activities, while SIN-1 with PKTs activities. The course of neutrophil apoptosis in vitro shows that different compounds depending on the mechanisms of NO release exert differential effects on apoptotic events. SNP and SIN-1 are involved in the process of bacterial killing by neutrophils. We conclude that NO released and its derivatives formed in the course of the interaction between neutrophils and bacteria are responsible for the enhancement of neutrophil antibacterial activity.