The article concerns study of the effect of antibody-mediated blockade of serotonin-modulating anticonsolidation protein (SMAP), being in linear relation with serotonin, on the formation of memory in the rats on the conditioned models of alternative running and 2-lever operant differentiation with food reinforcement, as well as on the level of nerve growth factor (NGF) in the brain structures. In the 1st series of studies in the rats, achieved 80% level of correct trials on the model of alternative running, through ELISA-test the level of SMAP was evaluated in the brain occipital and temporal cortex. Significant downregulation (p<0.001) of SMAP in the temporal cortex of the trained rats was noticed. In the 2nd and 3rd series of studies a single intra-cerebral administration of the anti-SMAP antibodies prior to learning sessions brought to much quicker (p<0.001) formation of the memory (50% level of correct trials), than in the intact and control (non-immune γ-globulins) animals, as well as to a significantly quicker decrease of latency of the first running towards the platform or lever (p<0.01). In the 4th series of studies 24 h later since intra-cerebral administration of anti-SMAP antibodies induced downregulation of NGF in the hippocampus (p<0.001) and left parietal cortex (p<0.001), whereas 3 days later downregulation of NGF in the left parietal cortex (p<0.001) and its upregulation in the hippocampus (p<0.001) were noticed. It is proposed that, promoting effects of antibodies-mediated blockade of SMAP on the formation of memory traces are related to its negative regulation of cellular differentiation