The therapeutic effect of quetiapine on cognitive impairment associated with 5-HT1A presynaptic receptor involved schizophrenia.

The cognitive impairment associated with schizophrenia is highly prevalent and affects the overall functioning of subjects. The stimulation of the serotonin 1A receptor is a primary characteristic of some atypical antipsychotic drugs. We measured the levels of cognitive impairment using the Morris water maze test and protein kinase A activity in hippocampal neurons on presynaptic and postsynaptic serotonin 1A receptors to investigate the effect of dizocilpine-induced cognitive impairment associated with atypical antipsychotic drugs in rats treated by quetiapine alone or combined with WAY100635/tandospirone. The results of the Morris water maze test presented evidence that quetiapine alone alleviated the cognitive impairment associated with atypical antipsychotic drugs induced by dizocilpine. However, quetiapine plus WAY100635 induced no improvement of cognitive impairment associated with atypical antipsychotic drugs. The results of protein kinase A assay suggested that neither quetiapine alone nor in combination with tandospirone, but not quetiapine plus WAY100635, raised protein kinase A activity in hippocampus neurons. The present study demonstrated the key role of presynaptic serotonin 1A receptors on the therapeutic effect of quetiapine on cognitive impairment associated with atypical antipsychotic drugs. Moreover, that protein kinase A activity in hippocampal cells is involved in the mechanism of quetiapine's effect on cognitive impairment associated with atypical antipsychotic drugs.