A pyridinium-substituted analog of the TRH-like tripeptide pGlu-Glu-Pro-NH2 and its prodrugs as central nervous system agents.

K. Prokai-Tatrai, M. Teixido, V. Nguyen, A. D. Zharikova, L. Prokai

Research output: Contribution to journalArticle

12 Scopus citations


A metabolically stable and centrally acting analog of pGlu-Glu-Pro-NH2 ([Glu2]TRH, a tripeptide structurally related to TRH (thyrotropin-releasing hormone)) was designed by replacing the amino-terminal pyroglutamyl residue with a pyridinium moiety. The analeptic action of the analog was used to optimize the efficacy of this novel CNS agent when administered intravenously in its CNS-permeable prodrug forms obtained via the reduction of the pyridinium moiety to the nonionic dihydropyridine and esterifying the central Glu with various alcohols. The maximum effect in antagonizing pentobarbital-induced narcosis in mice was achieved with the hexyl ester that was used subsequently for a comparative evaluation with a prodrug of the parent neuropeptide in the Porsolt swim test as a paradigm for antidepressant effect. The novel analog maintained its antidepressant potency but showed reduced analeptic action compared to [Glu2]TRH; thus, an increase in the selectivity of CNS-action was obtained by the incorporation of the pyridinium moiety.

Original languageEnglish
Pages (from-to)141-152
Number of pages12
JournalMedicinal chemistry
Issue number2
StatePublished - Mar 2005


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