An in vitro rat diaphragmatic fatigue model induced by combined hypoxic and hypercapnic acidosis and the effect of salmeterol.

Hypoxia or hypercapnia impairs diaphragmatic contractility and induces fatigue. However, little is known about the combined effect of hypoxic and hypercapnic acidosis (HHA) on diaphragmatic fatigue. In this study, a gas mixture (21% O2, 12% CO2 and 67% N2) was used to produce HHA-induced rat diaphragmatic fatigue.

Changes of 5-lipoxygenase pathway and proinflammatory mediators in cerebral cortex and lung tissue of sensitized rats.

Aim: To explore the change of 5-lipoxygenase (5-LO) pathway expression and proinflammatory mediators level of lung tissue and cerebral cortex, and the possible regulatory mechanism through central nervous 5-LO pathways to pulmonary inflammatory status in antigen repeated challenged rats.

Methods: Four groups of rats were treated as control, asthma model, asthma model treatment with dexamethasone (DXM, 0.5 mg/kg, i.

[Effect of inhaled cyclosporin A on antigen-induced airway inflammation in asthmatic rats].

Aim: To investigate the effect of inhalation of cyclosporin (CsA) on antigen-induced airway inflammation in Sprague-Dawley rats.

Methods: Rats were sensitized with antigen (ovalbumin, OA). After two weeks, the sensitized rats were pretreated with aerosol CsA (5, 10, 20 g x L(-1)), once per day for 7 days.

[Effects of cyclosporin A aerosol on airway hyperresponsiveness in rats].

Aim: To study cyclosporin A (CsA) aerosol for anti-airway hyperresponsiveness (AHR) in sensitized rats.

Methods: Sensitized Sprague-Dawley rats were given cyclosporin A (5, 20 g.L-1) and sodium cromoglycate (SCG, 20 g.

[A model for quantitative cigarette smoking and response of airways to cigarette smoke in guinea pigs].

Objective: To establish an animal model for quantitative cigarette smoking and to determine the acute response of airways to cigarette smoke in guinea pigs.

Methods: The device for inhaling quantitative cigarette smoking was made, which was double pass and single-direction with the minimum dead space. The changes of airway resistance(R(L))and dynamic lung compliance(Cdyn) in guinea pigs exposed to compound air consisting of 75% cigarette smoke and 25% oxygen were observed.

Comparison of bronchodilating and antiinflammatory activities of oral formoterol and its (R,R)-enantiomers.

Aim: To compare the bronchodilating and antiinflammatory effects of oral racemic formoterol (rac-FMT) and (R,R)-formoterol (R,R-FMT).

Methods: The changes of lung resistance (RL), dynamic lung compliance (Cdyn), and the accumulation of inflammatory cells in bronchoalveolar lavage fluids (BALF) induced by ovalbumin aerosol in sensitized guinea pigs and mice were investigated in vivo.

Results: Mean value increase of RL and mean value reduction of Cdyn from 1 to 30 min after antigen challenge were up to 101 %+/-34 % and 42 %+/-7 %, respectively.

Effects of cyclosporin A by aerosol on airway hyperresponsiveness and inflammation in guinea pigs.

Aim: To study cyclosporin A (CsA) by aerosol for anti-asthmatic effects in guinea pigs.

Methods: PC200 changes of lung resistance (RL) in the antigen-challenged sensitized guinea pig induced by acetylcholine (ACh) or histamine, and eosinophils changes in bronchoalveolar lavage fluid (BALF) and pulmonary histologic section induced by antigen in vivo in sensitized guinea pigs were investigated.

Results: Pretreatment with CsA 10 g/L and 20 g/L by aerosol but not with CsA 5 g/L, dexamethasone (DXM) 0.