Abstract
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.
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References
Wang, K., Han, W. S., Ten-year progress of bioinorganic chemistry in China (in Chinese), Beijing: Higher Education Press, 1997, 19–31.
Du, H. Z., Yang, P., Xue, S. W., Study of transmembrane La3+ movement in rat ventricular myocytes by the patch-clamp technique, Chinese Science Bulletin, 2002, 47(18): 1518–1522.
Yang, P., Gao, F., Mechanisms of Bioinorganic Chemistry (in Chinese), Beijing: Science Press, 2002, 576–584.
Ni, J. Z., Bioinorganic chemistry of rare earth elements (in Chinese), 2nd ed., Beijing: Science Press, 1995, 286–287.
Li, G. R., Chen, Y. Y., Mechanism of heterogeneous electrophysiology in heart and the relation to electropharmacology and texicology, Chinese Journal of Pharmacology and Toxicology (in Chinese), 2001, 15(2): 95–104.
Raman, M., Martin, M., A uniform enzymatic method for dissociation of myocytes from hearts and stomachs of vertebrates, Am. J. Physiol., 1985, 249: H1056-H1060.
Hamill, O. P., Marty, E., Neher, B. S. et al., Improved patch-clamp technique for high resolution current recording from cells and cell-free membrane patch, Pflugers Arch, 1981, 391: 85–100.
Zhou, J., Hao, X. M., Wang, Z. M. et al., Characterization of outward current in mouse ventricular myocytes, Acta Physiology Simca (in Chinese), 1995, 47(6): 535–543.
Michael, A., Jeanne, M. N., Characterization of two distinct depolarization-activated K+ currents in isolated adult rat ventricular myocytes, J. Gen. Physiol., 1991, 97: 973–1011.
Hill, B., Ionic channels of excitable membrane, Sundorland: Sinauner Associates Inc, 1984, 70–75.
Agus, Z. S., Iain, D. D., Martin, M., Divalent cations modulate the transient outward current in rat ventricular myocytes, Am. J. Physiol., 1991, 261: C310-C318.
Sanguinetti, M. C., Nancy, K. J., Lanthanum blocks a specific component of IK and screens membrane surface charge in cardiac cells, Am. J. Physiol., 1990, 259: H1881-H1889.
Mayer, M. L., Sugiyama, K., A modulatory action of divalent cation on transient outward current in cultured rat sensory neurons, Journal of Physiology, 1988, 396: 417–433.
Talukder, G., Harrison, N. L., On the mechanism of modulation of transient outward current in cultured rat hippocampal neurons by di- and trivalent cation, Journal of Neurophysiology, 1995, 73: 73–79.
Arnold, M. K., Cardiac ion channels, N. Engl. J. Med., 1993, 328: 1244–1251.
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Shaowu, X., Pin, Y. Effect of La3+ on myocardiac potassium channels revealed by patch-clamp technique. Chin.Sci.Bull. 50, 968–970 (2005). https://doi.org/10.1360/04wb0046
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DOI: https://doi.org/10.1360/04wb0046