Gene expression in the brain from fluoxetine-injected mouse using DNA microarray.

Abstract

Previously we have examined the effects of phencyclidine and clozapine upon the gene expression in the mouse brain. Recently, fluoxetine (Prozac) has been introduced for the therapeutic purpose as an antidepressant drug. Miledi et al. reported blockage of mouse muscle and neuronal nicotinic acetylcholine receptor by various concentrations of fluoxetine. Furthermore, Kobayashi et al. discovered that fluoxetine inhibits G protein activated inwardly rectifying G protein activated K(+) (GIRK) channels using Xenopus oocyte expression assay. From these experiments, we considered that it might be interesting to study the effects of fluoxetine on the gene expression in the mouse brain. After we have injected fluoxetine once a day into mouse for 20 days, we sacrificed mouse by decapitation and extracted RNA from mouse cerebral cortex. We used DNA microarray method for examining the gene expression in the brain. We found the downregulation of many spot signals in the fluoxetine-treated mouse, for example cholecystockinin and prostaglandin D2 synthase.