Abstract:

BACKGROUND: Accumulating evidence indicates that oxytocin plays an important role in social interactions. Previous studies also suggest altered oxytocin function in patients with schizophrenia and depression. However, few studies have examined the central oxytocin levels in these disorders.
METHODS: Cerebrospinal fluid (CSF) oxytocin levels were measured by ELISA in male participants consisting of 27 patients with schizophrenia, 17 with major depressive disorder (MDD), and 21 healthy controls.
RESULTS: CSF oxytocin levels of patients with schizophrenia or MDD did not differ significantly with healthy controls. The antidepressant dose or the Hamilton depression rating scale score did not significantly correlate with the oxytocin levels in MDD patients. CSF oxytocin levels in schizophrenic patients significantly negatively correlated with second generation antipsychotic dose (r=-0.49, P=0.010) but not with first generation antipsychotic dose (r=-0.13, P=0.50). A significant correlation was observed between oxytocin levels and negative subscale of PANSS (r=-0.38, P=0.050). This correlation remained significant even after controlling for second generation antipsychotic dose (r=-0.47, P=0.016).
CONCLUSIONS: We obtained no evidence of altered CSF oxytocin levels in patients with schizophrenia or those with MDD. However, lower oxytocin levels may be related to higher second generation antipsychotic dose and more severe negative symptoms in schizophrenia.

日本語要旨:

65名の男性被験者(統合失調症患者27名、大うつ病患者17名、健常対照者21名)に対し、髄液中のオキシトシン濃度を測定した。各群間でオキシトシン濃度に有意差は認めなかったが、統合失調症患者においては第二世代抗精神病薬の内服用量と髄液中オキシトシン濃度との間に有意な負の相関を認めた。また、統合失調症患者のPANSS陰性症状スコアと髄液中オキシトシン濃度との間に有意な負の相関がみられた。