Abstract: Objective:To investigate the effect of Longmu Guizhi decoction(LD) on locomotor activity and non selective attention of juvenile SHR(spontaneously hypertensive rat)——a rat model of attention deficit hyperactivity disorder.Methods:Forty-eight SHR male  were randomly divided into high-dose LD group, middle-dose LD group, methylphenidate control group and saline control group. All the SHRs were lavaged for 14 days. Locomotor activity and non selective attention were examined by open-field test and Làt maze test respectively before and after intervention.Results :In open-field test ,the number of square crossing and rearing after intervention of methylphenidate and decoctions in SHRs was significantly fewer than the saline group (P<0.01). The number of the above items in methylphenidate group was significantly fewer than middle-dose LD group (P<0.05). There was no difference between methylphenidate group and high-dose LD group（P>0.05).In Làt maze test, frequency of leaning against the wall after intervention of methylphenidate and decoctions in SHRs was significantly increased compared with the saline group (P<0.01), and that of high-dose LD group was significantly higher than the methylphenidate group and middle-dose LD group(P<0.05).Conclusion :Longmu Guizhi decoction can reduce locomotor activity and improve non-selective attention of ADHD model rats,which presents some kind of dose-effect relationship.

Key words: mild brain injury syndrome, Longmu Guizhi decoction, animal, experiment, rat