Survival of rats undergoing continuous bile drainage depends on maintenance of circadian rhythm of bile secretion

A novel model for external biliary drainage in rat orthotopic liver transplantation

Objective

The objective of this study was to establish a stable model of orthotopic liver transplantation with external biliary drainage in rats, to provide the possibility for dynamic detection of bile characteristics after transplantation.

Methods

Ninety-eight Sprague Dawley rats were divided randomly into a control group (n = 30) and an external drainage group (n = 68). Biliary extra-drainage group rats were established as follows: an epidural catheter was implanted into the common bile duct and an appropriate hose was connected from the outside. A stoma was made into the high jejunum, and a hose was implanted. Then the 2 hoses were induced to connect with each other in the subcutis of the right lateral abdominal wall.

Results

The operative success rate and 1-week and 2-week survival rates of the extra-drainage group were 94.1% (64/68), 88.2% (60/68), and 79.4% (54/68), respectively. Meanwhile, in the control group, the operative success rate and 1-week and 2-week survival rates were 93.3% (28/30), 90% (27/30), and 83.3% (25/30), respectively. There were no significant differences at any time between the 2 groups (p > 0.05).

Conclusions

The biliary extra-drainage model in rat orthotopic liver transplantation provides a novel, simple, and reliable method for dynamic collection of bile. The operation success rate was satisfactory. This model was successful and could be applied in various experimental studies.

An updated and simplified method for bile duct cannulation of rats

The single bile duct cannulated rat model was used for short-term intestinal absorption studies. Rats were randomly assigned to three groups: (A) bile duct cannulated, (B) control laparotomy and (C) no treatment. The body weight and health of the rats were monitored before and until day 5 after surgery, while bile flow was measured in group A on day 2. On the fifth day, tail vein blood was harvested, and alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and total bilirubin were quantified. Analysis of variance showed no significant difference between the groups for these parameters. This study demonstrated the suitability of a surgical rat model feasible for evaluation of the impact of bile in pharmacokinetic studies.

Rat auxiliary liver transplantation without portal vein reconstruction: comparison with the portal vein-arterialized model

Auxiliary liver transplantation (ALT) has been reintroduced in clinical cases recently and is now believed to be a viable alternative to orthotopic liver transplantation. To provide a simple rat ALT model for studying the physiological and immunological aspects of the ALT graft, a new ALT was performed, and the comparison between this new model and the portal arterialized one that was reported by other investigators was carried out. At first, we confirmed that liver could tolerate the deprivation of its portal flow well, using a portosystemic shunted rat model. The new rat ALT model, in which the ALT graft obtained its blood inflow only from the hepatic artery, was then performed. Our results demonstrated that 50% of the hepatic artery-alone ALT graft showed almost normal structure histologically at 1 month after grafting, with bile secretion preserved. By contrast, only 8% 1-month graft survival was noted in the portal arterialized group, and all grafts stopped bile secretion 1 week after operation. In conclusion, with arterial blood supply alone, the ALT graft survived and demonstrated normal bile secretion function for more than 1 month. Portal vein arterialization is not an appropriate way to establish the graft's blood supply if no pressure adjustment measures were taken in advance.