Dynamics of various integral characteristics of individual changes in ethanol resistance in isolated muscles of grass frog]

A study was made of the dynamics of the mean level of toxic ethyl alcohol (EA) (3.5 M) resistance, of the correlation between the initial individual level of this resistance and the value and shifting direction of the level, and of the pattern of correlation between levels of resistance in the pair sartoria muscles and variability of resistance level in muscles, kept in EA subtoxic solutions (0.87 and 1.09 M) for 240 min. Two-phase changes in the mean level of resistance in muscles were revealed that involved its increase by 20% within 60 min of maintenance in both EA concentrations, and followed by a decrease of this level by the end of observation. On the first steps of muscle maintenance in EA subtoxic solutions, a negative correlation was noticed between the initial level of resistance and the value and direction of its shifting, in addition to narrowing the range of variability of this level in muscles. All these events were accompanied by a decrease or fluctuations in the correlation coefficient between levels of resistance in the pair muscles. By the end of the experiment, the range of variability of the level of resistance was seen to increase, and the earlier negative correlation between the initial individual level of resistance and the value and direction of its shifting appeared to change for a positive one. Both processes preceded the decrease in the mean level of muscle resistance.