Involvement of TRK receptors in the nootropic effect of cycloprolylglycine

Background. The neuropeptide cycloprolylglycine (CPG) is an endogenous dipeptide analogue of the nootropic piracetam. It has been experimentally shown that CPG (designed and synthesized at the Federal State Budgetary Scientific Institution «Federal Research Center of Original and Promising Biomedical and Pharmaceutical Technologies») has a spectrum of pharmacological effects characteristic of piracetam. In studies aimed at studying the mechanisms of action of CPG, it was found that glutamate AMPA receptors and neutrophin Trk receptors are involved in the anxiolytic, neuroprotective and antihypoxic effects of CPG. However, the mechanism of nootropic action of CPG has not been studied.

Objective. To test the hypothesis about the involvement of Trk receptors in the nootropic effect of CPG in a model of amnesia in mice induced by the administration of scopolamine.

Material and methods. The nootropic activity of CPG (1 mg/kg, i.p.) was studied in a model of amnesia in mice induced by scopolamine (0.75 mg/kg, subcutaneously). A pharmacological inhibitory assay was used with the Trk receptor blocker K252a (5 μg/kg, i.p.). The severity of amnesia was assessed using the Novel Object Recognition (NOR) test.

Results. Scopolamine was found to impair novel object recognition in mice in the NOR test. CPG prevents the development of amnesia induced by scopolamine, and Trk receptor blocker K252a blocks this effect.

Conclusion. Trk receptors are involved in the nootropic effect of the neuropeptide CPG.

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