Ohgami M, Doerschuk C M, Gie R P, English D, Hogg J C
University of British Columbia Pulmonary Research Laboratory, St. Paul's Hospital, Vancouver, Canada.
J Appl Physiol (1985). 1991 Jan;70(1):152-7. doi: 10.1152/jappl.1991.70.1.152.
Previous studies of monocytes isolated from peripheral blood have suggested that the lung sequesters these cells and has an important role in monocyte kinetics. However, the lung also provides the first capillary bed encountered by these cells after intravenous injection. A major criticism of the previous reports is that the behavior of monocytes in the lung may be altered as a result of the isolation procedure. The present study addresses this question by comparing the distribution of isolated monocytes (87% pure) in various organs 10 min after they were injected into either the central venous or the arterial circulation. The data show that the extraction of monocytes on the first passage through the lung after intravenous injection was 86.5 +/- 1.5%. After the monocytes had circulated for 10 min, the lungs contained 35.5 +/- 2.5% of the cells after intravenous injection and 29.7 +/- 2.2% after intra-arterial injection (P greater than 0.05). The lung-to-blood recovery ratio after either intravenous or intra-arterial injection showed that the lung contained a marginating pool of monocytes that was five to seven times the size of the circulating pool. The retention of monocytes in a region of the lung was proportional to the regional erythrocyte transit time. The half-life of the radiolabeled monocytes in the circulation was approximately 25 h. We conclude that the lung contains a marginating pool of monocytes and speculate that they concentrate there in preparation for migration into the interstitium and air space of the lung.
先前对外周血分离出的单核细胞的研究表明，肺会隔离这些细胞，并且在单核细胞动力学中发挥重要作用。然而，肺也是这些细胞在静脉注射后遇到的第一个毛细血管床。先前报告的一个主要批评是，单核细胞在肺中的行为可能会因分离程序而改变。本研究通过比较分离出的单核细胞（纯度为87%）在注入中心静脉或动脉循环10分钟后在各个器官中的分布来解决这个问题。数据显示，静脉注射后单核细胞首次通过肺时的提取率为86.5±1.5%。单核细胞循环10分钟后，静脉注射后肺中含有35.5±2.5%的细胞，动脉注射后含有29.7±2.2%的细胞（P>0.05）。静脉注射或动脉注射后的肺血回收比表明，肺中含有一个边缘池，其中单核细胞的数量是循环池的五到七倍。单核细胞在肺的一个区域的滞留与该区域的红细胞通过时间成正比。循环中放射性标记单核细胞的半衰期约为25小时。我们得出结论，肺中含有一个单核细胞边缘池，并推测它们集中在那里，为迁移到肺的间质和肺泡腔做准备。
