Native Small Airways Secrete Bicarbonate

Evidence that Calu-3 human airway cells secrete bicarbonate.

The Calu-3 cell line is being investigated as a model for human submucosal gland serous cells. In a previous investigation of basal short-circuit current ( I sc) in Calu-3 cells, high levels of bumetanide-insensitive basal I sc (∼60 μA/cm2) were measured in cells grown at an air interface. Basal I sc was reduced only 7% by bumetanide, and the largest component of basal I sc required both Cl- an...

Assessing small airways disease.

A simple method of assessing smaller airways obstruction is easily available and could be used retrospectively. In contrast to the mean forced expiratory flow between 25 and 75% of forced vital capacity (FVC; FEF25–75%), which measures the mid-portion of exhalation ending at nearly the same time as the forced expiratory volume in one second (FEV1) in these subjects, the FEV3/FVC% or (1-FEV3/FVC...

Small airways obstruction syndrome.

STUDY OBJECTIVES To clarify the significance of a functional lung pattern characterized by a decreased vital capacity (VC) and an increased residual volume (RV), but with a normal FEV1/VC ratio. SETTING A university teaching hospital. SUBJECTS Patients with bronchial asthma, pulmonary emphysema, and small airways disease, and older subjects. MEASUREMENTS Measurements of static and dynamic...

Small airways, big challenge.

Treating the small airways.

The final article in this series evaluates the approaches undertaken to treating the small-airway region of the lungs and the clinical implications of inhaled therapy targeting the periphery in patients with asthma and chronic obstructive pulmonary disease.