Opposite changes in phosphoinositide-specific phospholipase C immunoreactivity in the left prefrontal and superior temporal cortex of patients with chronic schizophrenia

Background: Abnormalities in types of neurotransmitter signaling that are coupled with phosphoinositide-specific phospholipase C (PLC) have previously been reported in brains from patients with schizophrenia. PLC, a main component of this pathway, may be affected in schizophrenia. Methods: We immunoquantified PLC β1, γ1 and δ1 in the left prefrontal cortex and superior temporal cortex, nucleus accumbens and amygdala, and in the right superior temporal cortex of postmortem brains obtained from a total of 19 patients with schizophrenia and a total of 27 controls. Results: PLC β1 immunoreactivities were increased in the particulate fraction from the prefrontal cortex (by 64%), although they were decreased in the particulate fraction from the left superior temporal cortex (by 28%), as compared with the values in controls. There was no difference in PLC β1 immunoreactivities in the nucleus accumbens, the amygdala or the right superior temporal cortex between schizophrenic patients and controls. PLC γ1 and δ1 immunoreactivities did not differ between the two groups in any of the regions studied. Conclusions: Changes in PLC β1 immunoreactivities in the prefrontal and superior temporal cortex of patients with schizophrenia may reflect abnormalities in neurotransmissions via receptors that are coupled with the Gqα-PLC β1 cascade.