Preoperative internal biliary drainage is superior to external biliary drainage in liver regeneration and function after hepatectomy in obstructive jaundiced rats

Abstract

Objective: To examine the differences in regeneration rates and functions of the liver at the time of and after hepatectomy in obstructive jaundiced rats with preoperative external and internal biliary drainage.

Summary background data: The significance of biliary drainage before surgery is controversial in patients with obstructive jaundice.

Methods: After biliary obstruction for 7 days, rats were randomly divided into three groups: obstructive jaundice and hepatectomy (OJ-Hx), external biliary drainage and hepatectomy (ED-Hx), and internal biliary drainage and hepatectomy (ID-Hx). The OJ-Hx group underwent hepatectomy without biliary drainage; the other two groups underwent hepatectomy after biliary drainage for 7 days. At the time of hepatectomy, all rats were provided with internal biliary drainage. On days 0, 1, 2, 3, and 7 after hepatectomy, the DNA synthesis rate and the concentrations of adenine nucleotides and malondialdehyde in the liver were determined as markers of the hepatic regeneration rate, energy status, and lipoperoxide concentration, respectively. Portal endotoxin concentrations were measured and serum hyaluronic acid concentrations were determined as an indicator of hepatic endothelial function.

Results: The relative liver weight was significantly higher in the ID-Hx group than in the OJ-Hx group on days 1, 3, and 7 after hepatectomy and than in the ED-Hx group on days 1 and 2. The rate of hepatic DNA synthesis was significantly higher in the ID-Hx group than in the OJ-Hx and ED-Hx groups on day 1. The rate was similar in the ED-Hx and ID-Hx groups on day 2 but was significantly higher than in the OJ-Hx group. The hepatic malondialdehyde concentration was significantly higher on day 1 in the ED-Hx group than in the other two groups. It was lowest in the ID-Hx group throughout the study. Both biliary drainage procedures lowered the portal endotoxin concentration and serum hyaluronic acid concentration at the time of hepatectomy. The serum hyaluronic acid concentration was lowest in the ID Hx group. Hepatic adenine triphosphate concentrations and energy charge levels were similar among the three groups.

Conclusion: Although both external and internal biliary drainage before hepatectomy improved serum liver function tests, portal endotoxin concentration, and serum hyaluronic acid concentration at the time of surgery, preoperative internal biliary drainage was superior to external drainage, as evidenced by the better liver regeneration and function after hepatectomy.

Figure 1. Experimental design. n, number of rats.

Figure 2. Changes in relative liver weight. Relative liver weight (%) = 100 × residual liver weight/body weight at the time of sacrifice. All data are expressed as means ± SEM. ▪, OJ-Hx group. •, ED-Hx group. ▴, ID-Hx group. *p < 0.05; **p < 0.01 vs. the OJ-Hx group; †p < 0.01 vs. the ED-Hx group.

Figure 3. Changes in the hepatic DNA synthesis rate. The incorporation of [3H] thymidine into DNA was calculated as disintegrations per minute per microgram of hepatic DNA. All data are expressed as means ± SEM. ▪, OJ-Hx group. •, ED-Hx group. ▴, ID-Hx group. *p < 0.05; **p < 0.01 vs. the OJ-Hx group; †p < 0.01 vs. the ED-Hx group.

Figure 4. Changes in the hepatic MDA concentration. All data are expressed as means ± SEM. ▪, OJ-Hx group. •, ED-Hx group. ▴, ID-Hx group. *p < 0.05; **p < 0.01 vs. the OJ-Hx group; †p < 0.01 vs. the ED-Hx group.

Figure 5. Changes in the portal endotoxin concentration. All data are expressed as means ± SEM. ▪, OJ-Hx group. •, ED-Hx group. ▴, ID-Hx group. *p < 0.05 vs. the OJ-Hx group.

Figure 6. Changes in the serum hyaluronic acid concentration. All data are expressed as means ± SEM. ▪, OJ-Hx group. •, ED-Hx group. ▴, ID-Hx group. *p < 0.05; **p < 0.01 vs. the OJ-Hx group; †p < 0.01 vs. the ED-Hx group.