Obstructive jaundice was produced in 11 dogs by common bile duct ligation for 4 weeks, then biliary decompression was performed by bilioenteric anastomosis. Animals were regularly studied over the 2 months after decompression by the following methods: (1) serum biochemistry was monitored; (2) light microscopic changes in serial liver biopsies were graded; (3) the respiratory characteristics of isolated hepatic mitochondria, obtained by open liver biopsy, were studied using an oxygen micro-electrode system; (4) in vivo handling of an hepatobiliary imaging agent (diisopropyl iminodiacetic acid) was studied by dynamic liver scintiscanning. None of these liver assessments were normalized after 7 to 10 days of biliary decompression. Our study suggests that biliary decompression of patients with extrahepatic biliary obstruction requires long periods of time to enable major recovery of the abnormal liver function induced by biliary obstruction.