Modulation of GABA- and Glycine-Activated Ionic Currents with Semax in Isolated Cerebral Neurons.

Bulletin of experimental biology and medicine2018PMID: 29577196

View on PubMed DOI: 10.1007/s10517-018-4043-8

Animal StudySemax

Plain Language Summary

Semax was applied directly to isolated rat brain neurons to observe how it affects electrical signaling. It increased the strength of inhibitory GABA signals in cerebellar cells by nearly 150%, while reducing inhibitory glycine signals in hippocampal cells by more than half. These opposing effects on two different types of inhibitory signaling suggest Semax fine-tunes brain circuit activity through multiple pathways, with effects that appear to involve signaling cascades inside the cell rather than direct receptor binding.

Abstract

The concentration-clamp experiments with neurons isolated from the rat brain showed that nootropic and neuroprotective drug Semax added to perfusion solution at concentration of 1 μM augmented the amplitude of GABA-activated ionic currents in cerebellum Purkinje cells by 147±13%. In addition, Semax in perfusion solution (0.1 and 1 μM) diminished the amplitude of glycine-activated chloride currents in hippocampal pyramidal neurons down to 68 and 43% control level, respectively. Both potentiating and inhibitory effects developed slowly, and they were poorly reversible, which indicated a probable implication of second messengers in the observed phenomena. Semax accelerated the falling edge of glycine-activated current both after a short-term co-application with agonist and after addition of this peptide into perfusion solution.

Authors

Sharonova, I N; Bukanova, Yu V; Myasoedov, N F; Skrebitskii, V G

Keywords

GABAA receptorSemaxcerebellumglycine receptorhippocampus