Morphological determinants of peripheral lung mechanical changes induced by capsaicin
Data
1997-04-01
Tipo
Artigo
Título da Revista
ISSN da Revista
Título de Volume
Resumo
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 mu g/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, L-m and tissue distortion (standard deviation of the number of intercepts, SDI). Multiple regression analysis showed significant associations between pulmonary tissue resistance (R-ti 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 R-ti 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. (C) 1997 Elsevier Science B.V.
Descrição
Citação
Respiration Physiology. Amsterdam: Elsevier B.V., v. 108, n. 1, p. 63-72, 1997.