Specific Disruption of Memory Reconsolidation of Conditioned Food Aversion in Snails by DNA Synthesis Inhibitors.

Abstract

The involvement of DNA synthesis in the mechanisms of long-term memory reconsolidation in edible snails trained for conditioned food aversion was investigated. Administration of nucleoside analogs, such as 5-bromo-2'-deoxyuridine or 3'-azido-3'-deoxythymidine, which inhibit DNA synthesis, 1 h before or 1-3 h, but not 5 h after reminder with the conditioned stimulus led to memory impairment. One day after the inhibitor application and memory reactivation, a weakly expressed memory impairment (amnesia) was observed, which progressed over the next few days to the complete disappearance of behavioral memory expression. In snails with formed aversive memory for two food conditioned stimulus, a specific memory impairment was observed only for the stimulus that was paired with the presentation of an inhibitor during the reminder, while the memory for the other non-reactivated conditioned stimulus remained intact. It is suggested that DNA synthesis in the brain plays a specific role in the genetic mechanisms of reconsolidation and maintenance of long-term conditioned food aversion memory in snails.