0000000000951154
AUTHOR
J. Cortijo
Role of epithelium in agonist-induced contractile responses of guinea-pig trachealis: influence of the surface through which drug enters the tissue.
1. A method has been used in guinea-pig isolated tracheal rings to achieve selective drug entry from the adventitial or mucosal surface. A study has been made of the effects of epithelium removal on responses to spasmogens entering the tissue solely from the adventitial or the mucosal surface. 2. Cumulative concentration-response curves for KCl (1 to 100 mM), acetylcholine (0.1 microM to 10 mM) and histamine (1 microM to 1 mM) were constructed in intact and epithelium-denuded tracheal rings in circumstances where drug entry was unrestricted or restricted to the adventitial or mucosal surface. 3. Epithelium removal did not alter the responsiveness or sensitivity of tracheal rings to KCl eith…
Epithelium modulates the reactivity of sensitized guinea-pig trachea: influence of the surface of drug entry.
Abstract A technique by which drug access was restricted to either the mucosal or the adventitial surface of tracheal rings isolated from sensitized guinea-pigs was applied to study the role of the epithelium in modulating responses to KCl, acetylcholine, histamine and antigen (bovine serum albumin, BSA). Epithelium removal did not alter the responsiveness or sensitivity of tracheal rings to KCl. In contrast, a leftward shift occurred for concentration-response curves to acetylcholine (concentration ratio (CR) = 4·1), histamine (CR = 2·9) and BSA (CR = 33·9) entering from the mucosal surface of de-epithelialized trachea. This shift was not associated with changes in the maximal effect of th…
Palliative Treatment of Dyspnea With Epidural Methadone in Advanced Emphysema
This study investigated whether epidural methadone perfusion at the thoracic level can mitigate dyspnea in patients with advanced emphysema.Open-label clinical trial without a control group.University hospital.The inclusion criteria were a diagnosis of emphysema, basal dyspnea index (Mahler scale)or = 3, FEV(1)or = 35%, and no indication for pneumoreduction or lung transplantation surgery.An epidural catheter was inserted at the thoracic level connected to a perfusion pump for administering methadone (6 mg/24 h). Assessments were made at baseline, 1 week, and 1 month after catheter insertion.Pulmonary function tests were performed, and determinations were made of arterial blood gas levels, …