The aim of this study is to observe the effects of pentagastrin (P-Gas), CCK-8 and proglumide (PGM), which were used solely or in combination on choleresis in rats prepared with neck vein and hepatic-bile duct intubation. The results indicate that: 1) P-Gas does not provide cholecystic effect; 2) CCK-8 has a little stimulating effect on bile flow and output of bicarbonate; 3) PGM increases the bile flow and the outputs of biliary bicarbonate and chloride significantly, but it can not increase the bile acid output; 4) after administration of CCK-8 2.3 micrograms/(kg.h) iv infusion and PGM 200 mg ig in combination the outputs of bile flow, bicarbonates and chloride were greater than to PGM given alone, but after P-Gas 2 micrograms/(kg.h) was used together with PGM the outputs were less than to PGM given alone. The results suggest that PGM has a remarkable effect of choleresis and its mechanism may be attributed to bile acid independent fraction, while CCK-8 was only a weaker stimulant and P-Gas can not modify the bile flow and bile components. In addition, there may be a synergism effect between PGM and CCK-8 and an antagonist suppression between PGM and P-Gas on choleresis in the rat.