Neuronal change: Compensatory acclimation of the contribution of an electrogenic pump to the resting potential

Abstract

1. The resting potential of the lateral giant neuron in the buccal ganglia of the fresh water snailHelisoma trivolvis becomes more negative with an increase in temperature (Fig. 1). 2. The degree to which the resting potential varies over 3 to 30° C is dependent upon the previous acclimation temperature of the experimental subject (Fig. 6A). 3. Temperature acclimation (at 5 and 25° C) partially compensates for the temperature dependence of the resting potential. 4. The resting potential can be dissected into ionic permeability and metabolic pump components by the use of ouabain, a specific inhibitor of sodium pump activity (Fig. 2). The contribution of the sodium pump to the resting potential is found to be the main component responsible for the resting potential acclimation (Fig. 6B). 5. Such compensatory temperature acclimation would enable the lateral giant neuron to maintain its function as effector of salivary gland activity over a wide range of environmental temperatures.