Abstract: Objective To investigate the effects of icariin, a major active component of traditional Chinese herb Epimedium on schizophrenia animal model. Methods MK-801, a N-methyl-D-aspartate (NMDA) receptor antagonist, was intraperitoneally injected into mice to establish a schizophrenia animal model. The open field behavior test infrared detection system was used to measure the mobility of mice in order to find the best optimal dose. 40 mice were randomly divided in to control group, model group, risperidone group and icariin group with 10 mice in each group. The risperidone group and the icariin group were given 0.1 mg/kg risperidone and 50 mg/kg icariin respectively. All groups were injected with 0.6 mg/kg MK-801 0.1 ml intraperitoneally, except the control group. The total distance and the central distance within 210 minutes were tested. Results The total distance and the central distance were significantly longer in the model group than in the control group (P<0.001), and were shorter in the risperidone group than in the control group (P<0.05). The total distance was shorter in the icariin group than in the model group, but there was no significant difference (P=0.065); and the central distance was shorter (P= 0.037). There was no significant difference in both total distance and the central distance between the risperidone group and the icariin group (P>0.05). Conclusion Icariin may improve the positive and negative symptoms of schizophrenia mice, which may be beneficial to schizophrenia therapy.

Key words: schizophrenia, icarrin, N-methyl-D-aspartic acid receptor, MK-801, animal model, open field test, mice