药物对中枢神经系统(CNS)的活性作用直接取决于其透过血脑屏障。这一屏障是由含有一种连续的内皮基底膜与邻近紧密相连的内皮细胞层的选择性可透过的毛细血管所组成。脑毛细血管缺乏基底膜毛孔和存在于全身的细胞间裂缝,但CNS外的毛细血管管壁可转运直径 The drug’s activity on the central nervous system (CNS) depends directly on its passage through the blood-brain barrier. This barrier is composed of a selectively permeable capillary containing a continuous endothelial basement membrane adjacent to the adjacent endothelial cell layer. Brain capillaries lack the basement membrane pores and cell-cell fissures that are present throughout the body, but the capillary wall outside the CNS translocates to a diameter