Dolhnikoff M, Sakae R S, Saldiva P H, Martins M A
Department of Pathology (Laboratorio de Poluiçao Atmosferica Experimental), Faculty of Medicine, University of Sao Paulo, SP, Brazil.
Respir Physiol. 1997 Apr;108(1):63-72. doi: 10.1016/s0034-5687(97)02526-7.
We studied the morphological elements associated with airway and pulmonary tissue responses to capsaicin in mechanically ventilated guinea pigs. Lungs were excised and frozen in liquid nitrogen 3 and 20 min after capsaicin infusion (1 or 100 micrograms/kg i.v.). Using image analysis, we obtained contraction index (CI) and peribronchial edema area (CUFF) for both central (C) and peripheral airways (P). We also assessed alveolar size (mean linear intercepts, Lm) and tissue distortion (standard deviation of the number of intercepts, SDI). Multiple regression analysis showed significant associations between pulmonary tissue resistance (Rti) and CUFFP (p < 0.001); pulmonary dynamic elastance and SDI (p = 0.002); and airway resistance and CUFFC (p < 0.0001). Our results suggest that increases in Rti observed in guinea pigs after capsaicin infusion are primarily dependent on changes in the small airways, mainly peribronchiolar edema; the increase in lung elastance is related to distortion of parenchymal tissues; and large airway edema contributes significantly to airway resistance.
我们研究了机械通气豚鼠气道和肺组织对辣椒素反应的形态学因素。在静脉注射辣椒素（1或100微克/千克）后3分钟和20分钟，切除肺并在液氮中冷冻。使用图像分析，我们获得了中央气道（C）和外周气道（P）的收缩指数（CI）和支气管周围水肿面积（CUFF）。我们还评估了肺泡大小（平均线性截距，Lm）和组织变形（截距数量的标准差，SDI）。多元回归分析显示肺组织阻力（Rti）与CUFFP之间存在显著关联（p < 0.001）；肺动态弹性与SDI之间存在显著关联（p = 0.002）；气道阻力与CUFFC之间存在显著关联（p < 0.0001）。我们的结果表明，辣椒素注射后豚鼠Rti的增加主要取决于小气道的变化，主要是细支气管周围水肿；肺弹性的增加与实质组织的变形有关；大气道水肿对气道阻力有显著贡献。
