The contribution of vagal mechanisms to exercise-induced asthma has been studied in 10 adult asthmatic patients using the anticholinergic drug ipratropium bromide. Exercise tests were performed for eight minutes on a cycle ergometer and each individual's tests were standardised by matching oxygen uptake. Two tests were done on each of three study days, the first being without previous medicatio...

Dose-response relationships of the cholinergic antagonist, atropine methonitrate, and the beta-adrenergic agonist, salbutamol, were examined by cumulative dose techniques. A wet aerosol, 1.5 mg atropine methonitrate produced a maximum response. The response to 200 microgram of salbutamol from a pressurised aerosol was close to maximum. Secondly, the bronchodilator response of salbutamol microgr...

It has been demonstrated that propranolol has the ability to lower the ocular tension in patients with glaucoma when given by intravenous injectionpranolol has a possible disadvantage in that it produces local anaesthesia. (Propranolol also possesses membrane activity which is in part responsible for its action against cardiac arrhythmias. The local anaesthesia and membrane activity are distinc...

b2-Adrenoceptor agonists evoke rapid bronchodilatation and are the mainstay of the treatment of asthma symptoms worldwide. The mechanism of action of this class of compounds is believed to involve the stimulation of adenylyl cyclase and subsequent activation of the cyclic adenosine monosphosphate (cAMP)/cAMP-dependent protein kinase cascade. This classical model of b2-adrenoceptor-mediated sign...

Tiotropium-olodaterol, formulated in the Respimat soft-mist inhaler, is an inhaled fixed-dose combination (FDC) of a long-acting muscarinic antagonist (LAMA) and a long-acting β2-agonist (LABA), commercialized under the name of Spiolto or Stiolto. The efficacy of tiotropium-olodaterol 5-5 μg once daily in adult patients with COPD was documented in eleven large, multicenter trials of up to 52 we...

The role of histamine H1 and H2 receptors in the lung is not clear. H1 receptor blockade results in bronchodilatation and inhibition of histamine induced bronchoconstriction. H2 receptor blockade in vitro prevents the normal negative feedback of histamine on further mediator release in antigen challenge. Bronchospasm in guinea pigs given antigen challenge is enhanced by previous administration ...

The effects of (a) regular use for one week and (b) a single dose of a synthetic anticholinergic (ipratropium bromide) on lung mucociliary clearance and as a bronchodilator was ascertained in a controlled, double-blind, cross-over study in 12 patients with reversible airways obstruction (mean increase in FEV after isoprenaline: 17% range 10-50%). Two puffs from a metered dose inhaler of either ...

The particle size of bronchodilator aerosols may be important in determining the site of deposition in the lung and their therapeutic effect. The distribution of aerosols (labelled with technetium-99m diethylene triamine pentacetic acid) of two different particle sizes has been studied by gamma camera imaging. The particles had mass median aerodynamic diameters (geometric standard deviations) o...

Theophylline has been used in the treatment of airway diseases, for more than 50 years with benefit thought to be derived from its ability to elicit bronchodilatation. Recent evidence has, however, suggested that theophylline possesses anti-inflammatory activity. The molecular mechanism of action remains unclear, although inhibition of the phosphodiesterase (PDE) enzyme, an enzyme which catalyz...

Paradoxical effects (bronchoconstriction instead of bronchodilatation) have been reported after inhalation of beta2-mimetics in asthmatic children, and it has been suggested that this was due to osmolality and pH changes of the nebulizer solution. We tested commercially available nebulizer solutions and found osmolality changes after 5, 10 and 15 min of nebulization. Osmolality was measured in ...