Effect of Temperature on Electrolyte Metabolism of Isolated Frog Skin

A study is presented on the effect of temperature on unidirectional active ion transport, resting electrolyte equilibrium (electrolyte composition), and oxygen consumption in isolated frog skin. The aims were twofold: first, to find out whether the rate of active transport can be changed without affecting the Na(+) and K(+) balance of skin itself; second, to arrive at minimal DeltaNa/DeltaO(2) values by correlating quantitatively inhibition of active ion transport with inhibition of O(2) consumption. NaCl transport was maximal at 20 degrees C. At 28 degrees and at temperatures below 20 degrees , rate of NaCl transport was diminished. In many instances NaCl transport was diminished in skins which maintained their normal Na(+) and K(+) content. In several cases, however, neither rate of transport nor resting electrolyte equilibrium was affected; in other cases, both were. O(2) consumption decreased when lowering the temperature over the range from 28 to 10 degrees C. From a plot of log Q(OO2) against 1/T an activation energy of micro 13,700 cal. was calculated, valid for the range from 10 to 20 degrees C. It appeared that micro was smaller for temperatures above 20 degrees C. Working between 10 and 20 degrees , it was found that, on the average, 4 to 5 equivalents of Na(+) were transported for one mole of O(2) consumed in skins with undisturbed resting electrolyte equilibrium.