Somnogenic effects of L-stepholidine in mice / 中国药理学通报

ABSTRACT

Aim To set up a highly effective and automatic mouse sleep-wake bioassay system,and evaluate the system through analysis of the somnogenic effects of L-stepholidine(SPD),targeting at dopamine D1/D2 receptors in mice.Methods The animals were housed in an insulated and soundproof recording chamber maintained at a constant temperature and humidity on an automatically controlled 12 h light/12 h dark cycle.The electroencephalogram and electromyogram were recorded continuously for 48 hours and analyzed by SleepSign software.Saline was administered ip to the mice at 2100 on the first day,and SPD was given on the next day at the same hour.The vigilance state was analyzed based on the polygraphic recordings by the same software.Results The system has been demonstrated to be highly efficient and stable in recording and reliable in analyzing sleep-wake behavior in mice.With the aid of the sleep bioassay system,we found that SPD significantly increased the total time spent in sleep during dark period,and prolonged durations of non-rapid eye movement sleep episodes,with a concomitant reduction in amount and EEG power density of wakefulness.SPD rendered no effect on rapid eye movement sleep.Conclusion Through the reliable mouse sleep bioassay system,we found that SPD promotes non-rapid eye movement sleep but not rapid eye movement sleep in mice.