MICROVASCULATURE OF THE HUMAN LUNG / 解剖学报

ABSTRACT

The microvasculature of the lung of three humans was studied with the replicascanning electron microscopic method. The pulmonary arteriole belongs to microvasculature at the level of the respiratory bronchiole and gives out some side branches to the alveoli. The diameter of the arteriole is about 30-50 ?m. The arteriole divided into terminal arterioles, which accompanied with primary alveolar ducts. The diameter of the terminal arteriole is about 10-20 ?m, 17.35?1.62 ?m in average (n=30). There are obvious imprints of smooth muscles and endothelial nuclei on the surface of the casts of arteriole and terminal arteriole. The diameter of the alveolar capillary is 5.87?0.90 ?m in average (n=500). The proportion of the capillary area arround the alveole is 66?1.4%. There are two patterns of capillary network, i. e. long mesh and round mesh in type. The diameter of the mesh is (9.24?2.02)?(5.65?1.40) and 5.75?0.84 ?m, respectively. The distance of the mesh center is 17.13?1.74 ?m (long) and 11.52?1.12 ?m (short) in long mesh, and 11.63?0.88 ?m in round mesh. The capillary network of the long mesh located at the entrance and the base of the alveoli; and the round mesh in the area between them. The metaarteriole supplying the alveoli enters the alveoli at their entrance and thev venule draining the alveoli at their base. The distance between them is about 330 ?m.According to the microvascular architecture, the pulmonary microvasculature may be divided into three ordered units i. e. the alveolar, the alveolar duct, and the respiratory bronchiolar units.