The effects of nifedipine on respiratory mechanics investigated by theend-inflation occlusion method in the rat.

Context:Calcium channel blockers may theoretically exhibit relaxing effects not only on vascular smooth muscle but also on airway smooth muscle. Objective:To investigate possible effects of nifedipine on respiratory mechanics in the rat. Methods:Respiratory system mechanical parameters were measured by the end-inflation occlusion method in the ratin vivobefore and after the intraperitoneal administration of nifedipine. Results:We found that nifedipine affects respiratory mechanics, inducing a reduction of airway resistance and of respiratory system elastance, probably because of a relaxing action on airway and parenchimal smooth muscle cells. Conclusion:Should these results be further confirmed by human investigations, a possible role of nifedipine in pharmacological respiratory system’s diseases treatment may be suggested. [ABSTRACT FROM PUBLISHER]