The distribution of hepatic succinic dehydrogenase has been compared in common bile duct-ligated and control rats. In control cases, a gradient of succinic dehydrogenase activity is found within each liver lobule; periportal regions exhibit the highest level of enzyme activity, and the activity gradually decreases in a central direction. Centrilobular regions exhibit only slight activity.
However, after complete ligation of the common bile duct, this gradient gradually disappears from the lobule due to a gradual increase in succinic dehydrogenase activity in middle and central regions. By 18–19 days after ligation, a relatively high and uniform level of succinic dehydrogenase activity is displayed by all surviving parenchymal cells, regardless of position occupied within the lobule. The possible functional implications of this finding are discussed.