Pulmonary pharmacology & therapeutics
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Pulm Pharmacol Ther · Jan 2007
Randomized Controlled TrialThe effect of codeine on the Urge-to-Cough response to inhaled capsaicin.
We have shown previously in normal subjects that a sensory measure, the Urge-to-Cough rating, increases at concentrations of inhaled capsaicin that are lower than those necessary to elicit reflex cough. This finding suggests that the Urge-to-Cough may represent an index of the cough response. Research on cough in the human has most often employed challenge with inhaled capsaicin to induce reflex cough. ⋯ These results showed that the initial threshold for responding to capsaicin-induced cough is the perception of an Urge-to-Cough, followed by a motor cough response if the capsaicin is increased above the perceptual threshold. As the capsaicin concentration increases, both the perceptual need to cough and the cough motor response increase. The response of subjects to inhalation of capsaicin consisted of both a sensory component leading to perception of an Urge-to-Cough and motor cough behavior.
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Pulm Pharmacol Ther · Jan 2007
Controlled Clinical TrialThe effect of montelukast (10mg daily) and loratadine (10mg daily) on wheal, flare and itching reactions in skin prick tests.
Antileukotriene agents are widely used for the treatment of allergic conditions including bronchial asthma and allergic rhinitis. The influence of montelukast on skin reactivity has not been clearly evaluated. The aim of this study was to determine the effect of montelukast on wheal, flare and itching in skin prick tests (SPTs). ⋯ Our data show a tendency to suppressive effect of montelukast on flare and itching but not on wheal which is basic for SPT interpretation. We conclude that found suppression have little impact on clinical effectiveness of SPT as a diagnostic tool.
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Cigarette smoking has been associated with impaired endothelium-dependent relaxation responses in the brachial and coronary arteries (endothelial dysfunction). The aim of the present study was to determine if the airway circulation is also affected and if airway treatment has an effect on endothelial function. Airway blood flow (Q(aw)) responses to inhaled albuterol as an index of endothelial function were measured in age-matched healthy current smokers, healthy ex-smokers, ex-smokers with COPD and healthy lifetime non-smokers; in the ex-smokers with COPD, the albuterol responsiveness was repeated after a 4-week treatment with an inhaled glucocorticoid/beta(2)-adrenergic agonist combination drug. ⋯ While drug treatment per se did not change Q(aw) significantly, it restored albuterol responsiveness (+67.6+/-11.1%; p<0.05) in the ex-smokers with COPD. Thus, cigarette smoking is associated with endothelial dysfunction in the airway, with a partial recovery of endothelial function after smoking cessation in healthy ex-smokers but not in ex-smokers with COPD. In the latter, combined glucocorticoid/beta(2)-adrenergic agonist treatment restores albuterol responsiveness.
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Pulm Pharmacol Ther · Jan 2007
Randomized Controlled TrialCapsaicin exposure elicits complex airway defensive motor patterns in normal humans in a concentration-dependent manner.
The airway defensive response to tussive agents, such as capsaicin, is frequently assessed by counting the number of cough sounds, or expulsive events. This method does not identify or differentiate important respiratory events that occur in the respiratory muscles and lungs, which are critical in assessing airway defensive responses. The purpose of this study was to characterize the airway defensive behaviours (cough and expiration reflex) to capsaicin exposure in humans. ⋯ At higher concentrations (>50 microM) ER's with one or more expulsive events (ER1) appeared, and the number of CR's with three or more expulsive events (CR3) increased. The decrease in EMG activation and airflow measurements with each successive expulsive event suggests a decline in power and shear force as the number of expulsive events increased. Therefore, the airway defensive response to capsaicin is a complex motor pattern that functions to coordinate ER's and CR's with differing numbers of expulsive events possibly to prevent aspirations and keep air moving to promote clearance.
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Pulm Pharmacol Ther · Jan 2007
Nicotine activates cell-signaling pathways through muscle-type and neuronal nicotinic acetylcholine receptors in non-small cell lung cancer cells.
Nicotinic acetylcholine receptors (nAChR) are expressed on non-neuronal cell types, including normal bronchial epithelial cells, and nicotine has been reported to cause Akt activation in cultured normal airway cells. This study documents mRNA and protein expression of subunits known to form a muscle-type nAChR in non-small cell lung cancer (NSCLC) cell lines. In one NSCLC examined, mRNA and protein for a heteropentamer neuronal-type alpha3beta2 nAChR was detected in addition to a muscle-type receptor. ⋯ They also lead to downstream activation of MAPK and Akt. Nicotine may play a role in regulating survival of NSCLC cells and endogenous acetylcholine released locally in the lung and/or chronic nicotine exposure might play a role in NSCLC development. In addition, exposure of NSCLC patients to nicotine through use of nicotine replacement products or use of tobacco products may alter the efficacy of therapy with EGFR inhibitors.