RESUMO
The studies have been carried out in vitro on the colons of 25 rabbits. The material was collected according to the Garry and Gillespie technique. The preparations consisted of the distal region of the colon together with the branches of parasympathetic nerves (pelvic ones) and with the sympathetic nerve (hypogastric). The conductivity was studied by the method of stimulation of these nerves branches with the 10 V impulses, 5 s long frequency 50-100 Hz, every 2-4 minutes. Spontaneous colon motoricity was registered on the kymograph in the chamber with oxyzenized Krebs fluid, according to the Magnus method. 0.3-10.0 ml of the bile per 1 l of the Krebs fluid was administered to the chamber. The same quantities of the physiological salt solution were administered to the chamber as the control. As for the chemically pure biliary acids, the cholic, deoxycholic and chenodeoxycholic acids (Light) were administered in quantities 500-1500 mumoles/l of the Krebs solution, as well as litocholic acid (Serva) in the concentration 300-500 mumoles/l. The control was carried out exactly as previously described. It has been found out that bile can inhibit or stimulate the colon motoricity and the nerves conductivity, depending on its concentration. At the small concentration (0.3 ml/l of the Krebs fluid) the bile stimulated the spontaneous colon motoricity and the conductivity of the sympathetic as well as the parasympathetic nerves. The high concentration (10 ml/l) had the inhibition effect on the colon motoricity and suppressed the nerves conductivity. As for the biliary acids, the strongest inhibitory effect had the litocholic acid, the weaker inhibitory effect had the cholic and deoxycholic acids. The chenodeoxycholic acid suppressed the nerves conductivity but stimulated the colon motoricity and increased the constriction amplitude.