Postprandial changes in contractile activity and bile concentration in gallbladder of the dog
Takahashi, I.; Nakaya, M.; Suzuki, T.; Itoh, Z.
American Journal of Physiology 243(5): G365-G371
1982
ISSN/ISBN: 0002-9513 PMID: 7137353 Document Number: 184881
Postprandial continuous changes in contractile activity and bile concentration in the gallbladder were investigated in conscious dogs when they were fed every 12 h. Gallbladder contraction was measured by chronically implanted force transducers. The concentration of bile collected through tubes chronically implanted in the gallbladder was measured. The postprandial contractile pattern consisted of 4 different periods, and the gallbladder bile concentration was different in each of the 4 corresponding periods. In the immediate postprandial period (0.58 .+-. 0.05 h), contractile activity transiently increased with feeding followed by quiescence. The bilirubin concentration was increasing (3.6 .+-. 0.89 mg .cntdot. dl-1] .cntdot. 10 min-1). In the rhythmic contraction period (6.3 .+-. 0.32 h), phasic contractions with a sustained tonic rise were continued. The bilirubin concentration was continuously decreasing (-3.3 .+-. 0.30 mg .cntdot. dl-1 .cntdot. 10 min-1). In the irregular contraction period (5.3 .+-. 0.36 h), tonic contraction of varying force with phasic contractions superimposed occurred at irregular intervals. Bilirubin was concentrated in the 1st half (3.4 .+-. 0.57 mg .cntdot. dl-1 .cntdot. 10 min-1) and diluted in the 2nd half period (-3.7 .+-. 0.45 mg .cntdot. dl-1 .cntdot. 10 min-1). The interdigestive period was defined as the period after the termination of the 1st interdigestive migrating contractions in the stomach. During the 1st h, no contraction was observed, but the bilirubin concentration was progressively increased (7.7 .+-. 1.70 mg .cntdot. dl-1 .cntdot. 10 min-1). These findings concerning conscious animals provide a great deal of knowledge to aid in understanding the physiology of gallbladder function.