• electroconvulsive shock;
  • gene expression;
  • raphe nucleus;
  • serotonin transporter

Abstract The antidepressive actions of electroconvulsive shock (ECS) therapy are considered to involve altered neurotransmission of serotonin. In this study, we investigated the effects of acute and chronic ECS on 5-hydroxytryptamine (5-HT) transporter mRNA expression in rat raphe nucleus. We found that serotonin transporter (5-HTT) mRNA expression was decreased in 9 and 24 h after acute ECS and in 3, 9, 24 h and 2 weeks after chronic ECS in rat raphe nucleus. We presume that the adaptive change in 5-HTT mRNA expression is possibly related to the therapeutic efficacy of electroconvulsive therapy (ECT) on medication-resistant depression.