Effect of Temperature on Excitation-Contraction Coupling of the Bullfrog Atrium

Effects of Low Temperature on the Membrane Currents and Tension Components of Bullfrog Atrial Muscle

“…The depression was also reported in sheep Purkinje fiber and analyzed in detail by DUDEL and RUDEL (1970). Moreover, INaf is known not necessarily to contribute to the tension development in amphibian myocardium (VASSORT and ROUGIER , 1972;LEOTY and RAYMOND, 1972), and actually the positive inotropic effect of cooling was observed almost as normal in the presence of TTX (SAITO , 1975). Meanwhile, INas failed to produce any appreciable tension development and appeared depressed at low temperature (Fig.…”