ABSTRACT
Effects of temperature on the electrical properties of the Paramecium membrane were investigated under constant current and voltage-clamp stimulation. With cells cultured at 18 °C, the resting potential was largely stable with experimental temperatures varied over the range of 10–25 °C, whereas action potential amplitude and membrane input resistance were inversely related to temperature increases. During voltage clamp, the early calcium current was increased, the time-to-peak decreased, and the early conductance increased with temperature. Similar modifications of the culturing temperature did not affect the resting potential, input resistance and stimulus-response relationship of the action potential, but the early conductance was reduced with increase in temperature. Possible effects of long- and short-term temperature changes upon intraciliary calcium concentration are discussed.
