Differential effects of ziprasidone and haloperidol on immobilization stress-induced mRNA BDNF expression in the hippocampus and neocortex of rats

Recent in vivo and in vitro experiments have demonstrated that second-generation antipsychotic drugs (SGAs) might have neuroprotective effects. Ziprasidone is a SGA that is efficacious in the treatment of schizophrenia. In this study, we sought to analyze the effects of ziprasidone on the expression of the neuroprotective protein brain-derived neurotrophic factor (BDNF) in the rat hippocampus and neocortex, with or without immobilization stress. The effect of ziprasidone (2.5 mg/kg) on the expression of BDNF mRNA was determined by in situ hybridization in tissue sections from the rat hippocampus and neocortex. Haloperidol (1.0 mg/kg) was used for comparison. Haloperidol strongly decreased the expression of BDNF mRNA in both the hippocampal and cortical regions, with or without immobilization stress (p < 0.01). In contrast, the administration of ziprasidone significantly attenuated the immobilization stress-induced decrease in BDNF mRNA expression in the rat hippocampus and neocortex (p < 0.01). Ziprasidone exhibited differential effects on BDNF mRNA expression in the rat hippocampus and neocortex. These results suggest that ziprasidone might have a neuroprotective effect by recovering stress-induced decreases in BDNF mRNA expression.