The Role of the Two-Pore Domain Potassium Channel TREK-1 in the Therapeutic Effects of Escitalopram in a Rat Model of Poststroke Depression

Abstract

Aim: Poststroke depression (PSD) is one of the most common neuropsychiatric complications after stroke. TREK-1, a two-pore-domain potassium channel, has been implicated in the pathogenesis of stroke and depression. The aim of this study was to investigate whether TREK-1 plays a role in the therapeutic effects of the selective serotonin reuptake inhibitor (SSRI) escitalopram in a rat PSD model. Methods: The whole-cell patch-clamp technique was performed to assess the effect of escitalopram on recombinant TREK-1 currents in HEK293 cells. The expression of TREK-1 mRNA and protein was measured in the hippocampus and prefrontal cortex (PFC), and neural stem cell (NSC) proliferation was detected in the hippocampal dentate gyrus (DG) in PSD rats after 3 weeks of escitalopram administration. Results: Escitalopram reversibly inhibited TREK-1 currents in a concentration-dependent manner. Chronic treatment with escitalopram significantly reversed the reductions in weight gain, locomotor activity, and sucrose preference in PSD rats. The expressions of TREK-1 mRNA and protein were significantly increased in hippocampal CA1, CA3, DG, and PFC in PSD rats, with the exception of TREK-1 mRNA in hippocampal CA1. NSC proliferation was significantly decreased in hippocampal DG of PSD rats. Escitalopram significantly reversed the regional increases of TREK-1 expression and the reduction of hippocampal NSC proliferation in PSD rats. Conclusion: TREK-1 plays an important role in the therapeutic effects of the SSRI escitalopram in PSD model, making TREK-1 an attractive candidate molecule for further understanding the pathophysiology and treatment of PSD.