In vitro response of tracheal smooth muscle from hyperresponsive guinea pigs to celiprolol.

The use of beta-blockers is limited by adverse effects such as bronchospasm in asthmatics. third generation beta-blockers such as celiprolol may show better respiratory tolerability because they lack beta-blocker induced broncho-constriction. effect of celiprolol on the histamine induced contraction of tracheal muscle strips prepared from ovalbumin-sensitised guinea pigs was studied. using oxygenated krebs-henseleit solution as the nutrient medium,the trachealis muscle activity was measured with isometric force displacement transducer and recorded on 4-channel oscillograph. celiprolol 10(-4) m shifted the concentration-response curve of histamine downwards and to the right. mean of amplitude of contraction,percent responses and deviations when compared with the control group were significantly different (p < 0.05). celiprolol antagonised histamine-induced contractions of tracheal muscle of guinea pigs. so it may be considered safe in patients with asthma. however,further clinical evaluation and exploratory work is required.