[Effects of bile and bile acids on spontaneous motor activity of the small and large rabbit intestines in vitro].

Abstract

The aim of our study was to describe the effects of bile and bile acids action on the spontaneous motor activity of the rabbit small and large intestines. The following fragments of intestines were used: duodenum, jejunum, ileum, caecum and colon of 25 rabbits of both sexes, weighing 2-3 kg. The motor activity of the isolated fragments of the intestines was recorded by the suspension method in a 300 ml container with oxygenated Krebs' solution, temp. 37 degrees C (constant), pH 7.8. The intestine was connected with the miograph constructed according to the Gillespie method. Vesicular bile was given in the amounts 0.3-10 ml per 1 l of the Krebs' solution. Chemically pure bile acids were also given as follows: cholic acid (Light) and chenodeoxycholic acid (Light) in the amount 500-1500 mumol/l of the Krebs' solution and lithocholic acid (Serva)--300-500 mumol/l. 0.33 ml/l of the Krebs' solution of the bile caused the threshold reaction, and only in the jejunum caused distinct inhibition of the motor activity. In duodenum, ileum and colon the inhibition time was very short, intestines quickly regained initial activity, and, what is more, frequency and amplitude of spasms were even greater. Big doses of the bile usually inhibited the motor activity of the studied intestine fragments, eliminating completely--with the exception of caecum--the spasms' amplitude, without releasing any relaxation reaction. As for the bile acids, the strongest inhibiting effect had lithocholic acid but, unlike bile, it caused the relaxation reaction.