Consistent with dopamine supersensitivity, RGS9 expression is diminished in the amphetamine-treated animal model of schizophrenia and in postmortem schizophrenia brain

Abstract

It is known that RGS9-2 gene knockout mice show supersensitivity to DA and have a marked elevation in the proportion of DA D2 receptors in the high-affinity state for DA (D2High receptors). As this is a similar profile to that observed in the CNS from subjects with schizophrenia, we examined whether postmortem CNS tissue from subjects with the disorder and brain striata from an animal model of psychosis or schizophrenia (the amphetamine-sensitized rat) had altered levels of RGS9-2. The mRNA for RGS9-2 in 29 control hippocampi was 0.185 ± 0.015 fg per fg of β-glucuronidase mRNA (average ± SE), while that in 29 schizophrenia hippocampi was 0.145 ± 0.015 fg per fg of β-glucuronidase mRNA (avera..