Effect of Neuropeptide Y on Action Potential of Working Right Atrial Cardiomyocytes in Early Postnatal Ontogeny

The effects of neuropeptide Y (10 —9 -10 —6 M) on electrical activity of right atrial cardiomyocytes of rats aging 7, 21, and 100 days were examined in vitro . Neuropeptide Y affected the amplitude-temporal parameters of the action potential in these cells. It decreased the duration of repolarization phase in 7-day-old rats in concentrations of 10 —8 and 10 —7 M, in 21-day-old rats at 10 —8 and 10 —6 M, and in 100-day-old at 10 —6 M. The data indicate elevation of total membrane potassium current under the action of neuropeptide Y.