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 rat in vivo before 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.