Effect of La3+ on myocardiac potassium channels revealed by patch-clamp technique
The effect of La3+ on potassium channels in rat ventricular myocytes was investigated using the whole-cell patch-clamp recording mode. The Ca2+-independent voltage-activated outward K+ current was activated by the depolarizing pulse in enzymatically isolated rat ventricular myocytes. After addition of different concentrations La3+ to the bath solution, the outward K+ current was depressed gradually. The inhibition effect was in a concentrationdependent man-ner. The phenomena of the outward K+ current, being the main repolarizing current suppressed by La3+, suggest that the effect of lanthanides on myocardial function should be exploited further.
Keywordswhole-cell patch-clamp recording ventricular myocytes potassium channel La3+
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