Potential-dependent Ca2+ currents in isolated heart cells of hibernators.

Using the perforated patch-clamp technique, it has been shown that the potential-dependent Ca2+ current in cardiac myocytes of hibernators is not completely inhibited during hibernation. The residual Ca2+ current is classed as L-type Ca2+ current which is regulated by agonists and antagonists of Ca2+ channels. The effect of nifedipine, D600, isoproterenol and forskolin has been examined. It was found that isoproterenol affects the affinity of Ca2+ channels for the D600 blocker.