Prodynorphin and kappa opioid receptor mRNA expression in the cingulate and prefrontal cortices of subjects diagnosed with schizophrenia or affectivedisorders

The present study examined the prodynorphin and kappa opioid receptor mRNA expression levels in the anterior cingulate and dorsolateral prefrontal cor tices of subjects diagnosed with schizophrenia bipolar disorder, or major d epression as compared with normal controls without a psychiatric diagnosis. Multivariate analyses failed to reveal any differences in the mRNA express ion levels between the four diagnostic groups, though a group trend (non-si gnificant) was evident for the expression of the kappa opioid receptor and prodynorphin mRNAs in the prefrontal cortex. The mRNA expression levels wer e not associated with lifetime history of antipsychotic treatment or with s uicide as a cause of death. The results, however, suggested an influence of certain drugs of abuse on the prodynorphin cortical mRNA expression. Prody norphin mRNA expression levels were found to be elevated in individuals wit h a history of marihuana or stimulant use, but not alcohol. Overall, our da ta do not provide strong evidence for impaired prodynorphin or kappa opioid receptor mRNA levels in the dorsolateral prefrontal or cingulate cortices of schizophrenic, bipolar disorder, or major depressed subjects. (C) 2001 E lsevier Science Inc.