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. 1985 Nov;82(22):7796–7800. doi: 10.1073/pnas.82.22.7796

Ionic currents that generate the spontaneous diastolic depolarization in individual cardiac pacemaker cells.

E F Shibata, W R Giles
PMCID: PMC391421  PMID: 3877934

Abstract

An enzymatic dispersion procedure has been developed to obtain viable, spontaneously active single myocytes from cardiac pacemaker tissue: the bullfrog (Rana catesbeiana) sinus venosus. Recordings of time- and voltage-dependent Ca2+ and K+ currents have been made by using a single suction-microelectrode technique. The results show that two time- and voltage-dependent currents interact to modulate the slope of the pacemaker potential. These are: (i) the decay of a delayed rectifier K+ current and (ii) the activation of a Ca2+ current. In addition, the data strongly suggest that cardiac pacemaker tissue does not have an inwardly rectifying background K+ current.

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Selected References

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