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

Abstract

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 antipsychotic drug, against ketamine-induced cognitive disturbances. 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. Ketamine applications produced memory deficits in all tests and insignificantly increased MDA levels, which were alleviated by risperidone, EP, and combination treatments. 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.