Beta-adrenergic modulation of transient inward current in guinea-pig cardiac myocytes. Evidence for regulation of Ca2(+)-release from sarcoplasmic reticulum by a cyclic AMP dependent mechanism.

The results give support to the hypothesis that β-adrenoceptor-mediated positive inotropic and arrhythmogenic effects are, at least partly, due to a cyclic AMP-dependent regulatory mechanism modulating sarcoplasmic Ca 2+ -release