To continuously process neural activity underlying sensation, movement and cognition, the CNS requires a homeostatic microenvironment that is not only enriched in nutrients to meet its high metabolic demands but that is also devoid of toxins that might harm the sensitive neural tissues. This highly regulated microenvironment is made possible by two unique features of CNS vasculature absent in the peripheral organs. First, the blood–blood barrier, which partitions the circulating blood from the CNS, acts as a gatekeeper to facilitate the selective trafficking of substances between the blood and the parenchyma. Second, neurovascular coupling ensures that, following local neural activation, regional blood flow is increased to quickly supply more nutrients and remove metabolic waste. Here, we review how neural and vascular activity act on one another with regard to these two properties.

为了持续处理感觉、运动和认知背后的神经活动，CNS 需要一个稳态微环境，该微环境不仅富含营养以满足其高代谢需求，而且还没有可能损害敏感神经组织的毒素。这种高度调节的微环境是通过外周器官中不存在的 CNS 脉管系统的两个独特特征来实现的。首先，将循环血液与中枢神经系统隔开的血-血屏障充当看门人，以促进血液和实质之间的物质选择性运输。其次，神经血管耦合确保在局部神经激活后，局部血流量增加，以快速提供更多营养并清除代谢废物。这里，