BACKGROUND The use of beta blockers is limited by their ability to produce bronchospasm in asthmatics. Third generation beta-blockers like Nebivolol may show better tolerability because they may augment the release of nitric oxide (NO) from endothelial cells. However the involvement of NO in the respiratory effect of Nebivolol remains controversial. The present study, carried out on isolated tr...

BACKGROUND Inhalational insulin was withdrawn from market in 2007 due to its potential to produce airway hyper-reactivity and bronchoconstriction. So we explored the possible mechanism underlying the acute contractile effects of insulin and protective effects of beclomethasone against insulin induced airway hyper-responsiveness on isolated tracheal smooth muscle of guinea pig in vitro. METHOD...

We examined the effect of ethanol on single potassium channels derived from plasma membranes of bovine tracheal smooth muscles. The observed potassium channels had a conductance of 296 +/- 31 pS (mean +/- S.D.) in symmetrical 250 mmol/l KCl solutions, and exhibited a voltage- and Ca2+-dependence similar to BKCa channels. Ethanol at 50, 100 and 200 mM concentrations increased the probability of ...

BACKGROUND Airway instrumentation can evoke upper airway reflexes including bronchoconstriction and cough which can cause serious complications including airway trauma, laryngospasm or bronchospasm which may in turn lead to difficulty with ventilation and hypoxemia. These airway events are mediated in part by irritant-induced neuronal modulation of airway tone and cough responses. We investigat...

Peribronchial smooth muscle constriction causes airway stretch, an important mechanical force in developing lung. Little is known about factors influencing these spontaneously active muscle elements. We measured contractile activity of neurokinin (NK) receptors on fetal intrapulmonary smooth muscle by tracheal perfusion assay (n = 11). Injecting either capsaicin or the NK(2) receptor agonist [N...

Cortisol, a member of glucocorticoids, could potentiate the action of catecholamine by a non-genomic mechanism. Although this permissive effect has been well appreciated in the anti-asthmatic medication, the underlying signaling pathway has remained mysterious. Here, we show that extraneuronal monoamine transporter (EMT), a membraneous reuptake transporter for circulating catecholamine clearanc...