Abstract: | An increase in the amount of water-soluble proteins with the mobility of 0.56 in polyacrylamide gel was observed in the snail central nervous system at the early stages of long-term sensitization of the defensive reflex. Such an increase seems to be associated with the enhanced motor activity and a rise in the excitation level at this stage. 2 hours, 1 day and 3 days after long-term sensitization a dramatic decrease in the amount of water-soluble proteins with the mobility of 0.54, 0.42, 0.40 and membrane protein with the molecular weight of 24000 kD was observed. Such a decrease appears to reflect the stage nature of long-term sensitization and to be linked with shifts in the functional characteristics of some cellular elements of snail central nervous system. |