We investigated the in vivo and in vitro effects of lipopolysaccharide(LPS)-treatment (4 mg/kg, i.p.) on guinea-pig airway smooth muscle reactivity and epithelial bioelectric responses to methacholine (MCh) and hyperosmolarity. Hyperosmolar challenge of the epithelium releases epithelium-derived relaxing factor (EpDRF). Utilizing a two-chamber, whole body plethysmograph 18 h post-treatment, ani...

INTRODUCTION Asthma is major health burden throughout the world, and there are no therapies that have been shown to be able to prevent the development of disease. A severe respiratory paramyxoviral infection early in life has been demonstrated to greatly increase the risk of developing asthma. We have a mouse model of a severe respiratory paramyxoviral infection (Sendai virus, SeV) that mimics ...

In a mouse model of neutrophil elastase-induced bronchitis that exhibits goblet cell metaplasia and inflammation, we investigated the effects of intratracheal instillation of the MANS peptide, a peptide identical to the NH(2) terminus of the myristoylated alanine-rich C kinase substrate (MARCKS) on mucin protein airway secretion, inflammation, and airway reactivity. To induce mucus cell metapla...

In ten healthy, nonsmoking, non-atopic, young volunteers, specific airway conductance and bronchial response to aerosolized histamine were measured plethysmographically at intervals of 4.8 h during two periods of 24 h, i.e. one day without, the other with, a parasympatholytic aerosol (0.20-0.24 mg ipratropium bromide) inhaled 1 h before each measurement, in order to determine the role of the pa...

To evaluate whether increased airway reactivity affected the course of patients with cystic fibrosis (CF), we categorized 40 CF patients as to methacholine sensitivity and then evaluated their disease activity and natural history. Twenty methacholine reactors had more severe lung disease (lower S-K clinical scores and more impairment of pulmonary function) than did 16 nonreactive patients, and ...

We postulated that prolonged exposure to intermittent positive-pressure ventilation (IPPV) with high pressure (HIPPV) alone without hyperoxia promotes the development of airway hyperresponsiveness and remodeling. To test this hypothesis, young rats were ventilated under halothane anesthesia with HIPPV (maximum inspiratory pressure at 32-35 cmH2O in 70% nitrous oxide and 30% O2) for 3.5-4 h dail...

Measures of airway resistance (Raw) during deep inspiration (DI) suggest that asthmatic subjects possess stiffer, more reactive airway smooth muscle. There is evidence that one can enhance airway reactivity in healthy lungs by prohibiting DI for an extended period. The present study had two goals. First, we determined whether the maximum dilation capacity of asthmatic subjects depended on the r...

Exposure of humans to ambient levels of ozone (O(3)) causes inflammatory changes within lung tissues. These changes have been reported for the "initial" (1- to 3-h) and "late" (18- to 20-h) postexposure periods. We hypothesized that at the late period, when protein and cellular markers of inflammation at the airway surface remain abnormal and the integrity of the epithelial barrier is compromis...