The influence of pirenzepine in rat colonic mucus secretion.

The analysis of the effects of pirenzepine (0.2 mg/kg body weight) on S35 uptake of rat colonic mucus was studied by gel permeation chromatography. As it is well known, with this method two fractions - peak A and peak B - are clearly distinguished. In the included volume (peak B) pirenzepine decreases significantly the S35 uptake in the stimulated right colon. In the left one, the above effect was observed under both conditions: basal and stimulated. In the void volume (peak A), pirenzepine under basal conditions inversely shows an increase of the S35 uptake, whereas under stimulated conditions it reveals anticipated kinetic increase. Statistically, this data is less significant than that of peak B. All the findings demonstrated that muscarinic receptors of high sensitivity are present in rat colon.