Abstract
The duodenum and stomach of female rats, anaesthetized by urethane, were perfused separately and continuously with saline solution. Stimulation was performed by means of intravenous infusion of secretin, cholecystokinin-pancreozymin (CCK-PZ), and pentagastrin in a ‘step-test’, increasing the infused dosages in 20-minute periods. During basal secretion only acid and bicarbonate were detectable. High amounts of CCK-PZ induced the same maximal acid output as pentagastrin. All three hormones evoked the bicarbonate output in different intensities. The output of pancreatic enzymes was influenced only by CCK-PZ and pentagastrin. During the course of stimulation amylase showed a constant secretion rate. On the other hand, trypsin and chymotrypsin output increased to a peak and then decreased. In contrast to man and the dog, rather high doses of the different hormones are necessary to reach maximal secretion of acid, bicarbonate, and enzymes.