Inhibition of carbonic anhydrase by pirenzepine.

Previous work of the authors established a parallelism between gastric mucosa carbonic anhydrase (CA) activity and the values of acid secretion. It was shown that histamine (Ht) is a physiological activator of CA, and that there could be histaminic H2 receptors located on the molecule of CA. Pirenzepine (GZ) is a drug recently introduced in the therapy of gastroduodenal ulcer (GDU). Although its effect of decreasing acid secretion is clinically known, its mechanism of action remains uncertain. Original investigations are presented proving by in vitro and in vivo experiments on pure CA and on CA from human red blood cells and gastric mucosa that GZ is a strong inhibitor of CA. In this concept, GZ may be considered both an enzymatic inhibitor and an antagonist of histaminic H2 receptors.

Inhibition of gastric mucosa carbonic anhydrase by pirenzepine in patients with gastroduodenal ulcers.

Pirenzepine (Gastrozepin) is a drug recently introduced in the therapy of gastroduodenal ulcer (GDU). Although its effect of decreasing acid secretion is clinically known, its mechanism of action remains uncertain. The authors present investigations proving by in vitro experiments carried out on pure carbonic anhydrase (CA) and on CA from human gastric mucosa that GZ is a strong inhibitor of CA. In this acceptation, GZ may be considered both an enzymatic inhibitor and an antagonist of histamine H2 receptors.