Synaptic Mechanisms of Brain Serotonergic System Involved in Emotiogenic Regulation of Conditioned Activity

In “behavioral contrast” model under emotionally-positive and emotionally-negative effects appropriate changes in the performance of conditioning reflex were observed in animals that had received fluoxetine - selective inhibitor of serotonin reuptake by presynaptic terminals. This drug particularly slowed the rate of the performance in conditioning reflex when food reinforcement was reduced sharply that eliminated realization of the formed skills (frustration), increased the number of behavioral parameters (grooming, rearing), testifying the elevation of anxiety level. The possible mechanism of increase of anxiety level registered under emotionally-negative state of animals is supposed to be the result of concentration increase of the neurotransmitter in the synaptic cleft and activation of 5-HT1A and 5-HT2A receptors of serotoninergic system.