Long-term memory assessments after bee venom PLA
injection. A. Protocol indicating timing of injection and start of pre- and post-training tests with respect to the start of the first training session for both the conditioned (CS-UCS) and control (CS-DS) animals. B-D LTM assessment in animals injected 1 hr before training. In all control animals, rasping movements were similar upon application of the disturbance stimulus or conditioning stimulus (B). In contrast, in conditioned vehicle injected animals the number of rasping movements increased after application of the conditioning stimulus (C). The difference between the number of rasps induced by the conditioning stimulus minus the disturbance stimulus shows that there was a robust response to conditioning but only in the vehicle injected animals. None of the unconditioned animals or the PLA2 injected conditioned animals responded with significant feeding movements in the post-training test (D). These results indicate LTM impairment in snails injected with exogenous PLA2 1 hr before training. ***p < 0.001.