Martins M A, Dolhnikoff M, Zin W A, Saldiva P H
Laboratório de Poluição Atmosférica Experimental, Faculdade de Medicina, University of São Paulo, Brazil.
Am Rev Respir Dis. 1993 Feb;147(2):466-70. doi: 10.1164/ajrccm/147.2.466.
We studied the effects of capsaicin on airway and lung tissue mechanics in anesthetized and tracheostomized guinea pigs that were mechanically ventilated at constant tidal volume (8 ml/kg) and breathing frequency (60 breaths/min). Dose-response curves to intravenously infused capsaicin (1, 10, and 100 micrograms/kg) were performed (five animals for each dose, one dose per animal). We measured airflow, volume (by integration of the flow signal), tracheal pressure, and alveolar pressure with an alveolar capsule. Capsaicin induced a dose-dependent increase in airway resistance, tissue resistance, and dynamic elastance. The relationship between airway pressure and flow was fitted by a quadratic (Rohrer) equation. Airflow became more turbulent after infusion of capsaicin. After infusion of 100 micrograms/kg capsaicin, airway pressure (at flow rates of 10 ml.s-1) increased from 3.03 +/- 0.40 (mean +/- SEM) to 9.58 +/- 1.88 cm H2O, whereas the pressure corresponding to viscoelastic properties of lung tissue increased from 0.92 +/- 0.14 to 8.58 +/- 1.12 cm H2O. We conclude that infusion of capsaicin results in mechanical effects in both airways and pulmonary tissue.
我们研究了辣椒素对麻醉且气管切开的豚鼠气道和肺组织力学的影响，这些豚鼠以恒定潮气量（8毫升/千克）和呼吸频率（60次/分钟）进行机械通气。对静脉注射辣椒素（1、10和100微克/千克）进行了剂量反应曲线实验（每个剂量五只动物，每只动物一个剂量）。我们使用肺泡囊测量气流、容积（通过对流量信号积分）、气管压力和肺泡压力。辣椒素引起气道阻力、组织阻力和动态弹性的剂量依赖性增加。气道压力与流量之间的关系用二次（罗勒）方程拟合。注射辣椒素后气流变得更加紊乱。注射100微克/千克辣椒素后，气道压力（在流速为10毫升·秒⁻¹时）从3.03±0.40（平均值±标准误）增加到9.58±1.88厘米水柱，而对应于肺组织粘弹性特性的压力从0.92±0.14增加到8.58±1.12厘米水柱。我们得出结论，注射辣椒素会对气道和肺组织产生力学效应。
