Abstract
The possible interactions between serotonergic and glutamatergic systems during neural development and under the pathogenesis of depression remain unclear. We now investigated roles of 5-HT1A receptor in the mRNA expression of AMPA receptor subunits (GluR1 and GluR2) and brain-derived neurotrophic factor (BDNF) using primary culture of cerebral cortex of mouse embryos. Neurons at embryonic day 18 were cultured for 3days or 14days and then treated with 5-HT1A receptor agonist (8-OH-DPAT) for 3h or 24h. In neurons cultured for 3 days, 8-OH-DPAT treatment for both 3h and 24h increased the mRNA levels of BDNF and GluR1, but not GluR2. In neurons cultured for 14 days, however, 8-OH-DPAT had no effects on these mRNA levels. Next, we examined in vivo roles of 5-HT1A receptor by administration of 8-OH-DPAT to newborn mice. Twenty-four hours after the oral administration of 8-OH-DPAT, the mRNA expression of BDNF was decreased in the frontal cortex, but had no effects on the mRNA expression of GluR1 and GluR2. Taken together, the present study suggests that 5-HT1A receptor activation modulates mRNA expression of AMPA receptor subunit and BDNF in cortical neurons, and the effects are different between in vitro and in vivo.