On the functional consequences of bronchial basement membrane thickening

J Appl Physiol (1985). 2001 Sep;91(3):1035-40. doi: 10.1152/jappl.2001.91.3.1035.


Reticular basement membrane (RBM) thickness and airway responses to inhaled methacholine (MCh) were studied in perennial allergic asthma (n = 11), perennial allergic rhinitis (n = 8), seasonal allergic rhinitis (n = 5), and chronic obstructive pulmonary disease (COPD, n = 9). RBM was significantly thicker in asthma (10.1 +/- 3.7 microm) and perennial rhinitis (11.2 +/- 4.2 microm) than in seasonal rhinitis (4.7 +/- 0.7 microm) and COPD (5.2 +/- 0.7 microm). The dose (geometric mean) of MCh causing a 20% decrease of 1-s forced expiratory volume (FEV(1)) was significantly higher in perennial rhinitis (1,073 microg) than in asthma (106 microg). In COPD, the slope of the linear regression of all values of forced vital capacity plotted against FEV(1) during the challenge was higher, and the intercept less, than in other groups, suggesting enhanced airway closure. In asthma, RBM thickness was positively correlated (r = 0.77) with the dose (geometric mean) of MCh causing a 20% decrease of FEV(1) and negatively correlated (r = -0.73) with the forced vital capacity vs. FEV(1) slope. We conclude that 1) RBM thickening is not unique to bronchial asthma, and 2) when present, it may protect against airway narrowing and air trapping. These findings support the opinion that RBM thickening represents an additional load on airway smooth muscle.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asthma / pathology
  • Basement Membrane / pathology
  • Bronchial Hyperreactivity / pathology*
  • Bronchoconstrictor Agents / pharmacokinetics
  • Eosinophils / pathology
  • Female
  • Forced Expiratory Volume
  • Humans
  • Male
  • Mast Cells / pathology
  • Methacholine Chloride / pharmacokinetics
  • Pulmonary Disease, Chronic Obstructive / pathology
  • Respiratory Mucosa / pathology*
  • Rhinitis, Allergic, Perennial / pathology
  • Vital Capacity


  • Bronchoconstrictor Agents
  • Methacholine Chloride