Long- and short-acting @entity2162 agonists: interactions in XXXX contracted bronchi.

@entity1 @entity2162 @entity7284 @entity3045 @entity565 @entity2 @entity4183 @entity10453 @entity3044 @entity6410 @entity5402 @entity2263
The aim of this study was to systematically compare the interaction of the long-acting @entity2162 agonists @entity6410 and @entity10453 with short-acting @entity2162 agonists in contracted @entity1 bronchi. @entity1 bronchi were obtained at thoracotomy from @entity1 with @entity2 . @entity6410 or @entity10453 at concentrations inducing up to 92 and 94% of their maximal relaxant effect, respectively, were added to bronchial rings contracted with @entity5402 (10(-6) M). After a time period of 30 min, concentration-response curves for the short-acting @entity2162 agonists, @entity3045 , @entity4183 , @entity3044 and @entity7284 were recorded. Administration of equieffective concentrations of @entity10453 and @entity6410 , resulted in only @entity10453 inducing a shift to the right of @entity3044 , @entity4183 , @entity7284 and @entity3045 concentration-response curves. The rank order of shift was @entity3045 > @entity7284 > @entity4183 > @entity3044 . @entity6410 , up to concentrations of 3x10(-9) M induced submaximal relaxation resulting in no shift in short-acting @entity2162 agonist concentration-response curves. @entity10453 but not @entity6410 appears to antagonize the relaxation of @entity1 contracted bronchi induced by short-acting @entity2263 -agonists. These results obtained in vitro cannot be translated in clinical terms. This study, however, highlights the need for clinical studies on the interaction of long-acting and short-acting @entity2162 agonists in acute severe @entity565 .
