Summary
The effects of the Ca2+ agonist Bay K 8644 on outward potassium currents have been studied in single ventricular cells of chick embryo and aortic single cells of rabbit using the whole-cell patch clamp technique. Bay K 8644 was found to increase lK in both heart and aortic single cells. This effect of Bay K 8644 on both muscle was reversed by Mn2+ and blocked by 20 mM TEA. The Bay K 8644 potassium I/V curve of single heart cell had a N shape, which is Ca2+ dependent. These data strongly suggest that Bay K 8644 increases a gK(ca) in both aortic and heart muscle.
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Renaud, J.F., Bkaily, G., Benabderrazik, M. et al. Bay K 8644 induce enhancement of K+ current in both single heart cell and smooth muscle cell. Mol Cell Biochem 80, 73–78 (1989). https://doi.org/10.1007/BF00231005
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DOI: https://doi.org/10.1007/BF00231005