Regulation of Cardiac Calcium Current during Suppression of Second Messenger Intracellular Enzymatic Pathways
It is well established that membrane ionic channels in heart cells are up-regulated by enhanced activation of intracellular enzymatic cascades (1–3). However, less is known about channel regulation and modulation under conditions of depressed enzymatic activity such as might occur in the failing heart. In this study, we have developed protocols to suppress pertinent enzymatic activity in guinea pig ventricular myocytes, and examined the consequences on whole-cell calcium current (ICa) and its modulation.
KeywordsAdenosine HEPES Cardiol Acetylcholine Guanine
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