[Effect of pirenzepine on motility of Oddi's sphincter]

Pirenzepine (Gastrozepin) has a proven positive effect in the treatment of peptic ulcers by blocking the so called muscarinic acetylcholine receptors of the gastric glands. Reports of positive results with pirenzepine in the treatment of acute pancreatitis led to new discussions about its biological effects. It is thought that there are three ways by which pirenzepine acts in the pancreas. It decreases enzymatic secretion and it increases the secretion of sodium bicarbonate and water. Furthermore, it is said to have a spasmolytic effect on the sphincter of Oddi. To prove this spasmolytic effect we performed endoscopic manometry at the sphincter of Oddi with intubation of the pancreatic duct in 12 healthy patients. After two minutes of manometric registration of the normal sphincter activity 6 patients received 10 mg pirenzepine i.v. while a control group of 6 patients received 2 ml of 0.9% NaCl i.v. During the next 5 minutes the basal pressure of the sphincter, the amplitude of concentrations, as well as their frequency and duration were monitored. There were no changes noticed in the placebo group. However, pirenzepine caused a considerable decrease of the 4 manometric parameters of the sphincter of Oddi in all patients. Within 5 minutes the basal tonus fell from 14.3 +/- 5.1 mm of mercury to 9.0 +/- 6.0 (p less than 0.01). The frequency of contractions dropped from 5.8 +/- 2.7 per minute to 2.0 +/- 2.1 (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)