Treatment with β-adrenoceptor agonists does not fully overcome the symptoms associated with severe asthma. Serelaxin elicits potent uterine and vascular relaxation via its cognate receptor, RXFP1, and nitric oxide (NO) signaling, and is being clinically evaluated for the treatment of acute heart failure. However, its direct bronchodilator efficacy has yet to be explored. Tracheal rings were pre...

Pituitary adenylate cyclase-activating peptide (PACAP) is present in nerves in the vicinity of bronchial and vascular smooth muscle in the airways. At least one endogenous form of PACAP, PACAP 1-27, has high affinity binding sites in the lung, probably including cholinergic nerve terminals, bronchial smooth muscle, epithelial and mononuclear inflammatory cells. The mechanism of action for PACAP...

BACKGROUND The purpose was to assess tolerance to terbutaline after daily use of long-acting beta2- agonist (LABA) and further to evaluate two designs of reversibility test widely used in research and clinic in order to demonstrate tolerance. METHODS Twenty-eight asthmatics were given daily LABA in 12 weeks and were randomized to challenge test and either conventional reversibility test with ...

Forced expiratory spirograms were obtained before and for six hours after 25 subjects ingested ephedrine and placebo in a double-blind crossover study. Significant changes in the forced vital capacity (FVC) and the forced expiratory volume in one second (FEV1.0) were noted on days when ephedrine was administrated, while the mean forced expiratory flow during the middle half of the FVC (FEF25-75...

Salmeterol and formoterol are two long-acting beta2-agonists for inhalation, currently being used in clinical practice. The aim of the present study was to investigate the onset of action, duration of effect and potency of these two beta2-agonists in asthmatic patients. Patients (n=28) were included on the basis of salbutamol stepwise reversibility (100, 100 and 200 microg, given cumulatively; ...

BACKGROUND AND PURPOSE Marijuana smoking is widespread in many countries, and the use of smoked synthetic cannabinoids is increasing. Smoking a marijuana joint leads to bronchodilation in both healthy subjects and asthmatics. The effects of Δ(9) -tetrahydrocannabinol and synthetic cannabinoids on human bronchus reactivity have not previously been investigated. Here, we sought to assess the effe...

Activation of taste receptors (TAS2Rs) by bitter taste agonists has been reported to cause bronchodilation. The aim of this study was to extend the information on the effects of bitter taste agonists on responses induced by different contractile mediators in a standard airway physiology preparation. Isometric responses were assessed in guinea pig trachea (GPT). TAS2R agonists were administered ...

Clinically observed differences in airway reactivity and asthma exacerbations in women at different life stages suggest a role for sex steroids in modulating airway function although their targets and mechanisms of action are still being explored. We have previously shown that clinically relevant concentrations of exogenous estrogen acutely decrease intracellular calcium ([Ca(2+)](i)) in human ...

Deep inspirations (DIs) have a dilatory effect on airway smooth muscle (ASM) that helps to prevent or reduce more severe bronchoconstriction in healthy individuals. However, this bronchodilation appears to fail in some asthmatic patients or under certain conditions, and the reason is unclear. Additionally, quantitative effects of the frequency and magnitude of DIs on bronchodilation are not wel...

The aim of the study was to characterize pharmacokinetics of tiotropium solution 5 µg compared to powder 18 µg and assess dose-dependency of tiotropium solution pharmacodynamics in comparison to placebo. In total 154 patients with chronic obstructive pulmonary disease (COPD) were included in this multicenter, randomized, double-blind within-solution (1.25, 2.5, 5 µg, and placebo), and open-labe...