Abstract
INTRACELLULAR recording of electrical activity in the excised sartorius muscle of Hyla coerulea shows a negative after-potential of 20–25 mV. with a half-time of decay (t ½) of 8–12 m.sec. at 25° C. The time of recovery to resting potential level is increased to t 1/2 of 18–25 m.sec. when K+ is absent from the glucose–phosphate–Ringer medium. Successive Increases of K+ concentration up to 15 N/1,000 cause successive shortenings of repolarization time to t ½ 6 m.sec.1. These processes are faster by one-third in Rana catesbiana. The after-potential of Hyla muscle is prolonged, also, by reduction of Na+ in the medium to 20 M (t 1/2 15–20 m.sec.) or by increase of H+ to pH. 6.5, which gives t ½ of 28 m.sec.
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References
Macfarlane, W. V., J. Physiol., 119, 1P (1952).
Lorente de No, R., Studies from Rockefeller Inst. Med. Res., 131, 132 (1947).
Slater, E. C., Nature, 172, 979 (1953).
Slater, E. C., and Cleland, K. W., Biochem. J., 55, 566 (1953).
Bull, G. M., Carter, A. B., and Lowe, K. G., Lancet, ii, 60 (1953).
Brown, M. R., Currens, J. H., and Marchand, J. F., J. Amer. Med. Assoc., 124, 545 (1944).
Schatzmann, H. J., and Witt, P. N., J. Pharm. and Exp. Ther., 112, 501 (1954).
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MACFARLANE, W., MEARES, J. Modification of the After-Potential of Single Muscle Fibres by 2:4-Dinitrophenol. Nature 176, 403–404 (1955). https://doi.org/10.1038/176403a0
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DOI: https://doi.org/10.1038/176403a0
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