Kaplan J, Koehler R C, Terry P B, Menkes H A, Traystman R J
J Appl Physiol Respir Environ Exerc Physiol. 1980 Jul;49(1):9-15. doi: 10.1152/jappl.1980.49.1.9.
We studied the effect of lung volume on resistance through collateral pathways (Rcoll) and small airways (Rsaw) before and after the injection of methacholine into obstructed segments of intact dogs. Before methacholine, Rcoll decreased 15.0 +/- 4.9 (SE)% per cmH2O increase in transpulmonary pressure (Ptp) and Rsaw decreased 5.1 +/- 7.0 (SE)% per cmH2O increase in Ptp. Following methacholine, lung inflation resulted in similar decreases in Rcoll and Rsaw. The fall in Rcoll was significantly greater than the fall in Rsaw. When pressure in an obstructed segment (Ps) was increased with constant Ptp (nonhomogeneous inflation), Rcoll fell approximately half as much for each cmH2O increase in pressure compared to when Ptp was increased (homogeneous inflation). We conclude 1) that increases in lung volume have small effects on Rsaw so that there is a relative increase in flow through collateral channels serving obstructed poritons of lung and 2) that Rcoll is a function of the size of the obstructed segment that increases more under homogeneous than nonhomogeneous conditions.
我们研究了在向完整犬的阻塞节段注射乙酰甲胆碱前后，肺容积对通过侧支途径的阻力（Rcoll）和小气道阻力（Rsaw）的影响。在注射乙酰甲胆碱之前，经肺压（Ptp）每增加1 cmH2O，Rcoll降低15.0±4.9（SE）%，Rsaw降低5.1±7.0（SE）%。注射乙酰甲胆碱后，肺膨胀导致Rcoll和Rsaw出现类似程度的降低。Rcoll的下降显著大于Rsaw的下降。当在恒定Ptp（非均匀膨胀）情况下增加阻塞节段的压力（Ps）时，与增加Ptp（均匀膨胀）相比，压力每增加1 cmH2O，Rcoll下降幅度约为前者的一半。我们得出以下结论：1）肺容积增加对Rsaw影响较小，因此流经为肺部阻塞部分提供服务的侧支通道的血流相对增加；2）Rcoll是阻塞节段大小的函数，在均匀条件下比非均匀条件下增加得更多。
