Kirchner K K, McBride J T
Department of Pediatrics, University of Rochester School of Medicine and Dentistry, New York 14642.
J Appl Physiol (1985). 1990 Jan;68(1):187-92. doi: 10.1152/jappl.1990.68.1.187.
We have previously shown that airway cross-sectional area increases 15-20% after pneumonectomy in weanling ferrets by measuring bronchial casts. We have now reanalyzed these same casts to quantitate changes in airway length after pneumonectomy. In each cast the distance from each of 120 airways to the terminal bronchiole along its axial pathway was measured. The relationship between the logarithm of this distance and that of the fraction of the lobe subtended by an airway could be described by a quadratic equation with a correlation coefficient greater than 0.85. Subsegmental and more distal airways of postpneumonectomy animals were 33-47% longer than those of controls. Overall the main axial pathway of airways in the left lower lobes was 12% longer in operated animals, but this increase was primarily accounted for by an increase in the length of the more peripheral airways. Central airways were little if any longer in operated animals. After pneumonectomy in weanling ferrets, subsegmental and peripheral airway lengths increase to a greater degree than lung volume and airway cross-sectional area, whereas central airway lengths increase to a lesser extent if at all. The mechanisms responsible for this difference between central and intralobar compensatory airway growth are unknown.
我们之前通过测量支气管铸型表明，在幼龄雪貂肺切除术后，气道横截面积增加了15% - 20%。我们现在重新分析这些相同的铸型，以定量肺切除术后气道长度的变化。在每个铸型中，测量了120条气道中每条气道沿其轴向路径到终末细支气管的距离。该距离的对数与气道所占据肺叶部分的分数的对数之间的关系可用相关系数大于0.85的二次方程来描述。肺切除术后动物的亚段气道和更远端的气道比对照组的长33% - 47%。总体而言，手术动物左下叶气道的主要轴向路径长12%，但这种增加主要是由更外周气道长度的增加所致。手术动物的中央气道即使有延长也很轻微。在幼龄雪貂肺切除术后，亚段气道和外周气道长度的增加程度大于肺容积和气道横截面积，而中央气道长度即使增加也幅度较小。中央气道和叶内代偿性气道生长之间这种差异的机制尚不清楚。
