Risperidone and ethyl pyruvate have protective effects against ketamine-induced cognitive impairments in mice

Abstract

OBJECTIVE: Ketamine, an N-methyl D-aspartic acid receptor antagonist drug, is reported to produce memory disruptions. The aim of this study was to investigate the protective effects of ethyl pyruvate (EP), a pyruvic acid derivative, and risperidone, an atypical anti-psychotic drug, against ketamine-induced cognitive disturbances.

MATERIALS AND METHODS: A passive-avoidance test, a novel object recognition test, and a modified elevated plus maze test were used to assess memory functions. Hippocampal malondialdehyde (MDA) levels were measured to determine the oxidation levels.

RESULTS: Ketamine applications produced memory deficits in all tests and insignificantly increased MDA levels, which were alleviated by risperidone, EP, and combination treatments.

CONCLUSIONS: Increased oxidative stress and neurotransmission imbalance can be responsible for ketamine-induced memory disruptions. With its antioxidant effects, EP may be helpful to reduce cognitive impairments related to schizophrenia either alone or in combination with antipsychotics.