ABSTRACT
The present study was undertaken to examine the effect of paroxetine, a selective serotonin reuptake inhibitor, on the phosphorylation of cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) in the rat brain. Single administration of paroxetine significantly induces the phosphorylation of CREB in the rat frontal cortex and hippocampus in a time-dependent manner. Repeated administration of paroxetine attenuates CREB phosphorylation in response to acute paroxetine challenge. These findings suggest that the enhancement of intracellular signal transduction after the activation of serotonin receptors may be attenuated after chronic paroxetine treatment, and this attenuation may be, at least in part, involved in the therapeutic efficacy of paroxetine.
