In-vitro Effect of Pirenzepine on Motility of Canine Gall-bladder

Abstract
The action of pirenzepine as an antimuscarinic drug has been investigated on motor responses of muscle strips in the canine gall-bladder. Pirenzepine was further used to examine whether gall-bladder motor responses to synthetic sulphated cholecystokinin octapeptide (CCK-8) are sensitive to pirenzepine. Pirenzepine (10−9-10−5 M) antagonized muscle contractions in response to acetylcholine (10−9-10−2 M) and CCK-8 (10−11-10−6 M) in a significant manner. These findings indicate that pirenzepine is a potent antagonist of two substances that are the principal contractile mediators of gall-bladder contraction and suggest that long-term administration of pirenzepine could contribute to stasis of the gall-bladder.