Regulation of cardiac L-type Ca channels in planar lipid bilayers by G proteins and protein phosphorylation.


We have studied the effects of activated G proteins (Gs alpha and Gi1 alpha), adenosine 3',5'-cyclic monophosphate-dependent protein kinase (PKA), and okadaic acid on L-type Ca channels incorporated from porcine ventricular sarcolemma into planar lipid bilayers. Channel activity evoked by membrane depolarizations diminished to extremely low levels within 2… (More)