A role for M(2) and M(3) muscarinic receptors in the contraction of rat and human small airways.

Large airway bronchoconstriction acts mainly through cholinergic pathways via muscarinic M3 receptors with some contribution from M2 receptors. By contrast, the mechanisms of small airway contraction are largely unknown. This study used precision cut lung slices to examine the role of muscarinic M2 and M3 receptors in the contractile response of rat and human small airways.

In vitro pharmacological characterization of vilanterol, a novel long-acting β2-adrenoceptor agonist with 24-hour duration of action.

Vilanterol trifenatate (vilanterol) is a novel, long-acting β(2)-adrenoceptor (β(2)-AR) agonist with 24 h activity. In this study, we describe the preclinical pharmacological profile of vilanterol using radioligand binding and cAMP studies in recombinant assays as well as human and guinea pig tissue systems to characterize β(2)-AR binding and functional properties. Vilanterol displayed a subnanomolar affinity for the β(2)-AR that was comparable with that of salmeterol but higher than olodaterol, formoterol, and indacaterol.

Involvement of IL-13 in tobacco smoke-induced changes in the structure and function of rat intrapulmonary airways.

Chronic obstructive pulmonary disease (COPD) involves disease of small airways with an increase in airway smooth muscle sensitivity to spasmogens and with structural changes described as airway remodeling. We investigated the effect of tobacco smoke (TS) exposure on the structure and function of small airways in rats and the role of IL-13 in this response. Precision-cut lung slices (230-280 microm) were prepared from male Sprague-Dawley rats after acute (3 d) or chronic (8 or 16 wk) daily exposure to TS or air.

Pharmacological characterization of indacaterol, a novel once daily inhaled 2 adrenoceptor agonist, on small airways in human and rat precision-cut lung slices.

Indacaterol is a novel once daily inhaled beta(2) adrenoceptor agonist in clinical development. This study compared the properties of indacaterol with salmeterol, formoterol, and albuterol on small airways in precision-cut lung slices from human and rat contracted with carbachol and serotonin, respectively. In human lung slices, the rank order of potency was formoterol >/= salmeterol > indacaterol > albuterol, respectively.

Polypeptide N-acetylgalactosaminyltransferase activity in tracheal epithelial microsomes.

Pig tracheal epithelium, a site of extensive mucin biosynthesis, contained polypeptide N-acetylgalactosaminyltransferase activity directed towards L-threonine residues. The enzyme preparation was broadly similar in properties to preparations from other tissues, e.g.