The activity of the histaminergic system decreased and the decrease might be one of the compensatory mechanisms for maintenance of the normal sleep in the null mice lacking DPR.

• DPR基因敲除型小鼠脑中组胺能神经活性显著降低,这一变化可能是该种小鼠尚能维持正常睡眠的代偿机制之一。