The effect of temperature on muscle resting potential in some insects

The effect of temperature on muscle resting potential was studied in Acheta domesticus, Leptinotarsa decemlineata and Tenebrio molitor. The experiments were performed using the conventional microelectrode method and specific physiological solution for each insect species. The measurements were taken at three temperature levels: +/- 4 degrees C, +/- 20 degrees C and +/- 35 degrees C. Placing the preparations into a bath at 4 degrees C caused in all three species a rapid decrease of the muscle resting potential (+/- by 1/3). Increased temperature (+/- 35 degrees C) led to a transient increase of the resting potential (10 min after placing in the solution), and then a decrease of the potential below the control values. The possible mechanisms of these findings based both on ionic gradients, permeabilities and metabolic activity are discussed.