Conditioned taste aversion modifies persistently the subsequent induction of neocortical long-term potentiation in vivo

• Published in: Neurobiology of learning and memory Vol. 95; no. 4; pp. 519 - 526
• Main Authors: Rodríguez-Durán, Luis F., Castillo, Diana V., Moguel-González, Minerva, Escobar, Martha L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.05.2011; Elsevier; Elsevier BV
• Subjects: Amygdala - physiology; Animal cognition; Animal memory; Animals; Avoidance Learning - physiology; Behavioral psychophysiology; Biological and medical sciences; Brain; Conditioning, Classical - physiology; CTA; Fundamental and applied biological sciences. Psychology; Insular cortex; Long-Term Potentiation - physiology; LTP; Male; Metaplasticity; Neocortex - physiology; Neural Inhibition - physiology; Neurobiology; Neurons; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Rats; Rats, Wistar; Retention (Psychology) - physiology; Rodents; Synapic plasticity; Synaptic Transmission - physiology; Taste; Synapic plasticity; CTA; LTP; Insular cortex; Metaplasticity; Cerebral cortex; Induction; Central nervous system; Long term potentiation; Gustative system; Encephalon; In vivo; Gustation; Synaptic plasticity; Taste; Conditioned aversion
• ISSN: 1074-7427; 1095-9564
• DOI: 10.1016/j.nlm.2011.03.003

► CTA training prevents the subsequent induction of LTP in the Bla-IC projection. ► CTA training modifies the synaptic strength of the Bla-IC projection. ► CTA training prevents the IC-LTP induction for at least 120 hrs after CTA training. ► Inhibition of CTA consolidation with anisomycin prevents the CTA effect on IC-LTP. The ability of neurons to modify their synaptic strength in an activity-dependent manner has a crucial role in learning and memory processes. It has been proposed that homeostatic forms of plasticity might provide the global regulation necessary to maintain synaptic strength and plasticity within a functional dynamic range. Similarly, it is considered that the capacity of synapses to express plastic changes is itself subject to variation dependent on previous experience. In particular, training in several behavioral tasks modifies the possibility to induce long-term potentiation (LTP). Our previous studies in the insular cortex (IC) have shown that induction of LTP in the basolateral amygdaloid nucleus (Bla)-IC projection previous to conditioned taste aversion (CTA) training enhances the retention of this task. The aim of the present study was to analyze whether CTA training modifies the ability to induce subsequent LTP in the Bla-IC projection in vivo. Thus, CTA trained rats received high frequency stimulation in the Bla-IC projection in order to induce LTP 48, 72, 96 and 120h after the aversion test. Our results show that CTA training prevents the subsequent induction of LTP in the Bla-IC projection, for at least 120h after CTA training. We also showed that pharmacological inhibition of CTA consolidation with anisomycin (1μl/side; 100μg/μl) prevents the CTA effect on IC-LTP. These findings reveal that CTA training produces a persistent change in the ability to induce subsequent LTP in the Bla-IC projection in a protein-synthesis dependent manner, suggesting that changes in the ability to induce subsequent synaptic plasticity contribute to the formation and persistence of aversive memories.