Kawakami Y, Nishimura M, Kusaka H
First Department of Medicine, School of Medicine, Hokkaido University, Sapporo, Japan.
J Appl Physiol (1985). 1991 Apr;70(4):1781-6. doi: 10.1152/jappl.1991.70.4.1781.
Tracheal dimensions at total lung capacity (TLC) and residual volume (RV) were analyzed roentgenographically in 17 pairs of male adolescent twins (mean age 16.3 yr; 12 monozygotic pairs and 5 dizygotic pairs). Genetic factors dominated environmental traits in intra- as well as extrathoracic tracheal width at RV. Extrathoracic tracheal width at TLC was also governed by genetic components. Intrathoracic tracheal depth (anteroposterior diameter), length, and cross-sectional area did not seem to be genetically controlled at TLC and RV. Intrathoracic tracheal cross-sectional area increased by 14.4% and became more elliptical from RV to TLC, owing mainly to an increase in tracheal depth (16.7%). Increments from RV to TLC in tracheal depth but not width correlated with increases in lung width, depth, and height. Intrathoracic trachea was elongated 14% in association with increase in lung height from RV to TLC. At TLC, extrathoracic tracheal width was larger than intrathoracic tracheal width, but this dimension did not differ at RV. These results indicate that genetic factors influence, at least at RV, the tracheal rings more strongly than membranous parts. Intrathoracic tracheal depth but not width increases during inspiration in accordance with increase in lung volume. Extrathoracic tracheal width widens more than intrathoracic trachea from RV to TLC.
对17对男性青少年双胞胎（平均年龄16.3岁；12对同卵双胞胎和5对异卵双胞胎）进行了X线摄影分析，以研究肺总量（TLC）和残气量（RV）时的气管尺寸。在残气量时，遗传因素在胸内和胸外气管宽度的环境特征中占主导地位。肺总量时的胸外气管宽度也受遗传因素控制。在肺总量和残气量时，胸内气管深度（前后径）、长度和横截面积似乎不受遗传控制。从残气量到肺总量，胸内气管横截面积增加了14.4%，并且变得更椭圆，这主要是由于气管深度增加了16.7%。从残气量到肺总量，气管深度而非宽度的增加与肺宽度、深度和高度的增加相关。随着从残气量到肺总量肺高度的增加，胸内气管伸长了14%。在肺总量时，胸外气管宽度大于胸内气管宽度，但在残气量时这一尺寸没有差异。这些结果表明，遗传因素至少在残气量时对气管环的影响比对膜性部分的影响更强。吸气时，胸内气管深度而非宽度随着肺容积的增加而增加。从残气量到肺总量，胸外气管宽度比胸内气管增宽得更多。
