The Response of Human Erythrocytes to NO-Stimulation

Background: The research of recent decades has demonstrated the participation of nitrogen monoxide in various metabolic and regulatory intracellular cascades. However, the majority of works in this field seeks to detect the functional activity of endogenous NO. In opposite, the biological effects of the exogenous nitrogen monoxide have been insufficiently looked into. That is why the aim of the present study was a comprehensive assessment of the effect of various NO-stimulation options on the state of human erythrocytes in vitro.

Methods: This study used 15 healthy subjects’s (20-45 years old) blood samples divided into five portions. The first portion was allocated as the control; the second portion was treated with a flow from the Plazon apparatus (800 ppm NO); the third portion was processed in a stream tenfold diluted with air (80 ppm NO), fourth portion – with a gas mixture containing 75 ppm NO and fifth portion was introduced with a solution of dinitrosyl iron complexes (DNIC, 3 mM). In all blood samples we estimated the peroxide resistance of erythrocyte, levels of malonic dialdehyde and lactate, superoxide dismutase activity, activity of lactate dehydrogenase and aldehyde dehydrogenase.

Results: We stated that blood processing with high NO dose (800 ppm) causes elevation of peroxide resistance of erythrocyte, levels of malonic dialdehyde and lactate with inhibition of activity of superoxide dismutase, lactate dehydrogenase (in forward reaction) and aldehyde dehydrogenase. In opposite, low NO dose (75 ppm) and DNIC induced the decreasing of peroxide resistance of erythrocyte and stimulation of enzymes catalytic activity.

Conclusion: The study has revealed that low doses of gaseous NO and a solution of DNIC produce the most favorable effect on the oxidative and energy metabolism, as well as on the activity of aldehyde dehydrogenase of erythrocytes.