再生障碍性贫血(简称再障)是由骨髓造血功能低下所致,其发病机制尚未完全阐明。目前,多数人认为有:①造血干细胞数量减少及质的缺陷;②免疫机制异常:③微环境缺陷;④血窦障碍。本文着重讨论微循环缺陷学说。长期以来,已知骨髓造血微环境与造血细胞的生长及分化增殖起着重要作用,造血干细胞在造血组织中需要特殊环境,即造血微环境,而造血干细胞与造血微环境有很密切的关系,两者的关系犹如种子与土壤。骨髓微环境包括微循环及基质,骨髓造血活动与血液供应又有密切关系,骨髓的血液供应来自滋养动脉,滋养动脉不断分枝,由小动脉直接流入窦状隙。在黄骨髓中,小动脉分枝后形成毛 Aplastic anemia (referred to as aplastic anemia) is caused by bone marrow dysfunction, the pathogenesis has not been fully elucidated. At present, most people think: ① reduce the number of hematopoietic stem cells and quality defects; ② immune system abnormalities: ③ micro-environmental defects; ④ sinus disorders. This article focuses on the theory of microcirculation defects. For a long time, it is known that bone marrow hematopoietic microenvironment plays an important role in the growth and differentiation and proliferation of hematopoietic cells. Hematopoietic stem cells require a special environment in the hematopoietic tissue, that is, the hematopoietic microenvironment, and the hematopoietic stem cells have a close relationship with the hematopoietic microenvironment. The relationship between the two is like seeds and soil. Bone marrow microenvironment including microcirculation and matrix, bone marrow hematopoietic activity and blood supply are closely related, the blood supply of bone marrow from nourishing the artery, nourish the artery constantly branching, the arterioles directly into the sinusoid. In the yellow bone marrow, the arterioles branch to form hairs