Hiroki Kikuyama

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It has been hypothesized that glutamatergic neurotransmission is related to the therapeutic effect of antipsychotic drugs. To test this hypothesis, we measured by use of the Western blot technique the polypeptide levels of NMDA receptor subunits, that is, NMDAR1, 2A, 2B, and 2C, in several regions of the rat brain after chronic treatment with haloperidol(More)
Increasing evidence has supported the hypothesis of a neurodevelopmental component in the etiology of schizophrenia. Recently, several independent microarray gene expression studies have revealed downregulated expression of myelin-related genes in the postmortem brains of schizophrenia patients. Complete myelination of the cortex has been observed to occur(More)
OBJECTIVES To identify the reliable connectivity between causal genes or variants with an abnormality expressed in a certain endophenotype has been viewed as a crucial step in unraveling the etiology of schizophrenia because of the considerable heterogeneity in this disorder. METHODS According to this practical and scientific demand, we aimed to(More)
INTRODUCTION Schizophrenia is a heritable disorder, however clear genetic architecture has not been detected. To overcome this state of uncertainty, the SZGene database has been established by including all published case-control genetic association studies appearing in peer-reviewed journals. In the current study, we aimed to determine if genetic variants(More)
Atypical psychosis with a periodic course of exacerbation and features of major psychiatric disorders [schizophrenia (SZ) and bipolar disorder (BD)] has a long history in clinical psychiatry in Japan. Based upon the new criteria of atypical psychosis, a Genome-Wide Association Study (GWAS) was conducted to identify the risk gene or variants. The(More)
We investigated the possible association between genetic polymorphisms in the dopamine receptor and serotonin transporter genes and the responses of schizophrenic patients treated with either risperidone or perospirone. The subjects comprised 27 patients with schizophrenia who were clinically evaluated both before and after treatment. The genotyping of the(More)
OBJECTIVE Medication adherence is important in the treatment of schizophrenia, and critical periods during treatment may be associated with relapse. However, the relationship between adherence and duration of outpatient treatment (DOT) remains unclear. The authors aimed to clarify the relationship between adherence and DOT at a psychiatric hospital in(More)
To reduce the number of patients with depression, biomarkers for clarifying psychiatric disorders are warranted. Numerous candidates have been proposed; however, near-infrared spectroscopy (NIRS) with multi-channel probes and a dexamethasone/corticotropin-releasing hormone (DEX/CRH) test are still surviving for practical demand. Thirty-one outpatients with(More)
OBJECTIVE Electroconvulsive therapy (ECT) is a reasonable option for intractable depression or schizophrenia, but a mechanism of action has not been established. One credible hypothesis is related to neural plasticity. Three genes (Oct4, Sox2, c-Myc) involved in the induction of induced pluripotent stem (iPS) cells are Wnt-target genes, which constitute a(More)
INTRODUCTION Electroconvulsive therapy (ECT) is currently regarded as a significant treatment option for intractable psychiatric disorders, such as catatonic schizophrenia or treatment-resistant depression; however, the underlying molecular mechanism for its therapeutic effect remains obscure. METHODS Employing microarray analysis (Human Genome U133 Plus(More)