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 ΔNa/ΔO(2) values by correlating quantitatively inhibition of active ion transport with inhibition of O(2) consumption. NaCl transport was maximal at 20°C. At 28° and at temperatures below 20°, 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°C. From a plot of log Q (O(O2)) against 1/T an activation energy of µ 13,700 cal. was calculated, valid for the range from 10 to 20°C. It appeared that µ was smaller for temperatures above 20°C. Working between 10 and 20°, 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.