[The electrical characteristics of the command and motor neurons during the acquisition of a conditioned defensive reflex and the development of long-term sensitization in snails].

The mechanisms of conditioning of the defensive pneumostome closure reflex and long-term sensitization were studied at the level of electrical characteristics of the command and motor neurons. A significant decrease in membrane and threshold potentials in the command neurons was observed after the acquisition of the defensive reflex and long-term sensitization. These potentials decreased to a greater extent in the snails subjected to conditioning after the sensitization. Changes in the critical depolarization level for the action potential generation and its amplitude were insignificant. Thus, the observed phenomena testify to an increase in membrane excitability of the command neurons. Similar changes were not found in the motor neurons.