The Effect of Peptide Semax, an ACTH(4-10) Analogue, on Intracellular Calcium Dynamics in Rat Brain Neurons.

Bulletin of experimental biology and medicine2025PMID: 41171324

View on PubMed DOI: 10.1007/s10517-025-06501-z

Animal StudySemax

Plain Language Summary

When applied to rat brain tissue, Semax increased the frequency of spontaneous calcium activity in hippocampal neurons — a type of electrical signaling important for memory and learning. It did not, however, affect calcium entry through acid-sensing channels in cerebellar neurons, suggesting its neuroprotective effects work through a different mechanism in those cells. The findings help pin down where in the brain Semax acts and how its protective effects are initiated.

Abstract

We studied the effects of Semax on spontaneous fluctuations of intracellular calcium ion concentration [Ca]in pyramidal neurons on hippocampal slices and on proton-induced increase in [Ca]in cerebellar granule cells in cerebellar slices. Application of Semax (1 μM), significantly increased the frequency of spontaneous [Ca]fluctuations in the pyramidal layer cells of the hippocampal CA1 field, but had no significant effect on proton-stimulated increase in [Ca]in cerebellar granule cells. These data provide insight into the localization of cellular targets and elucidate the dynamics of the initial stages of interaction between the peptide and the hippocampal neuronal network. The primary mechanism of the neuroprotective effect of Semax appears to be unrelated to attenuation of calcium entry through acid-sensing ion channels in cerebellar granule cells.

Authors

Kolbaev, S N; Sharonova, I N; Skrebitsky, V G

Keywords

Semaxacid-sensing ion channelscalcium imagingcerebellar and hippocampal neurons