The stabilizing effect of Arg and NO in the regulation of L-type Ca²⁺ currents in cardiac cells

In experiments on the rat cardiocytes it is shown that presence of arginine in cell incubation and secretion media stabilizes amplitude of basal L-type Ca²⁺ currents and decreases response variability under action of this current regulators. Response stabilization is determined by the balanced effect on L-channels of the secondary messengers cAMP and cGMP due to assisted by arginine activation of NO- and cGMP-involving reaction cascades. Under such conditions L-channel regulation with participation of PKG becomes more expressed, while generated by β-adrenoreceptor activation current is completely compensated by acetylcholine.