Lockhart A, Dinh-Xuan A T, Regnard J, Cabanes L, Matran R
Laboratoire de Physiologie Respiratoire, Faculté de Médecine Cochin Port-Royal, Paris, France.
Am Rev Respir Dis. 1992 Nov;146(5 Pt 2):S19-23. doi: 10.1164/ajrccm/146.5_Pt_2.S19.
Resistance to gas flow of an airway is a function of both airway smooth muscle tone and thickness of the airway wall internal to the outer ring of airway smooth muscle. Schematically, the increase in airway resistance caused by shortening of airway smooth muscle may be potentiated by a concomitant increase in airway wall thickness caused by vasodilation of the bronchial vessels and/or microvascular leakage. Conversely, bronchial vasoconstriction may limit to some extent the increase in resistance to gas flow caused by airway smooth muscle shortening and/or congestion and edema of the airway wall. Many endogenous paracrine mediators, putatively involved in asthma and bronchial hyperresponsiveness, have both bronchomotor and vascular effects. The overall effects on resistance to airflow of endogenous or exogenous agents depend not only upon pre-existing airway smooth muscle tone and pre-existing condition of bronchial vessels but also upon two factors that facilitate microvascular leakage, namely, inflammation of the airway wall and outflow pressure of the bronchial circulation, which is close to left atrial pressure.
气道对气流的阻力是气道平滑肌张力和气道平滑肌外环内部气道壁厚度的函数。示意性地，气道平滑肌缩短引起的气道阻力增加可能会因支气管血管舒张和/或微血管渗漏导致的气道壁厚度同时增加而增强。相反，支气管血管收缩可能在一定程度上限制气道平滑肌缩短和/或气道壁充血及水肿引起的气流阻力增加。许多可能参与哮喘和支气管高反应性的内源性旁分泌介质具有支气管运动和血管效应。内源性或外源性物质对气流阻力的总体影响不仅取决于预先存在的气道平滑肌张力和支气管血管的预先存在状况，还取决于促进微血管渗漏的两个因素，即气道壁炎症和接近左心房压力的支气管循环的流出压力。
