Ketamiinin vaikutukset TrkB-ERK1/2-signalointiin kortikaalineuronien primaariviljemissä
Year: 2026
Type: article
Abstract: The dissociative anesthetic ketamine exerts rapid and sustained antidepressant effects at subanesthetic doses, proposed to be caused by an increase in glutamatergic activity and engagement of brain-derived neurotrophic factor (BDNF) signaling, tropomyosin receptor kinase B (TrkB) and extracellular signal regulated kinase 1 and 2 (ERK1/2). Early data on primary cortical neurons also demonstrated these concentration-dependent effects, but the results have not been replicated despite recent efforts. In this study, we examined the concentration-dependent effects of ketamine on TrkB and ERK1/2 phosphorylation (pTrkB and pERK1/2) in primary mouse cortical neuron cultures at 14 days in vitro (DIV14). Using western blot analysis, we measured pTrkB at Y816 and Y515, and pERK1/2 at mono- and dual-phosphorylation states (pERK1/2 pan) and only the dual phosphorylation state (pERK1/2 dual). Despite the cultures responding robustly to exogenously applied BDNF, exposure to sub-micromolar concentrations of ketamine did not upregulate pTrkB or pERK1/2. Instead, at 500 nM pTrkB-816 was downregulated and treatment with a higher ketamine concentration (10 μM) resulted in downregulation of pERK1/2, although corresponding pTrkB measurements were not obtained. Pharmacological modulation of GABAergic activity using picrotoxin selectively upregulated pERK1/2 dual, whereas diazepam downregulated both pERK1/2 pan and pERK1/2 dual. Together, these findings indicate that sub-micromolar ketamine concentrations do not increase the phosphorylation of TrkB or ERK1/2 in mouse primary cortical neuron cultures that retain functional responsiveness to BDNF and partially to GABAergic activity modulation. Instead, 500 nM ketamine concentration downregulates TrkB-816 phosphorylation and higher ketamine concentration downregulates ERK1/2 phosphorylation. Further validation of the western blot protocol is needed to characterize the different phosphorylation states of TrkB and ERK1/2. Combining this with multiwell-electrode array (mw-MEA) measurements would aid in the applicability of TrkB-ERK1/2 signaling results to the disinhibitory effect of ketamine seen in vivo, which may be difficult to model in vitro due to limitations in the complexity of the cultures’ biological mechanisms and the temporal limitations of experimental design and western blot analysis.
Source: Työväentutkimus Vuosikirja
Author: Velhonoja, Aarni
Language: English
Subfield: Pharmacology (medical)
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7198335802