NONPARENCHYMAL CELLS IN CHRONICALLY HYPERINSULINEMIC LIVER ACINI OF DIABETIC RATS, WITH SPECIAL REGARD TO HEPATIC STELLATE CELLS

Background/Aims: An increase in proliferative activity and other disti nct hepatocellular alterations - resembling preneoplastic foci and pro gressing to hepatocellular tumors - have been shown to develop in live r acini draining the blood from islets of Langerhans, transplanted thr ough the portal vein into the liver of streptozotocin-diabetic rats. M ethods: Altered and unaltered liver acini were investigated for possib le changes in hepatic stellate cells 4-76 days after islet transplanta tion. Results: Corresponding to a significant increase in the hepatoce llular volume, the volume density of total nonparenchymal cells was si gnificantly reduced in altered compared to unaltered liver acini, With regard to the total nonparenchymal cell volume, the hepatic stellate cell fraction was not different, whereas the fraction of Kupffer cells was significantly reduced and the fraction of sinusoidal endothelial cells was significantly increased in altered compared to unaltered liv er acini, respectively. The volume density as well as the single volum e of the hepatic stellate cell mitochondria increased significantly in altered compared to unaltered liver acini. Hepatic stellate cell lipi d droplets did not show significant differences between altered and un altered liver acini. lit situ hybridization for hepatocyte growth fact or mRNA showed no differences in intensity of the specific signals in hepatic stellate cells of altered versus unaltered liver acini. The tr ansplanted islets were negative for hepatic growth factor mRNA. Conclu sions: The results suggest that hepatic growth factor production by he patic stellate cells or by islet cells is not relevant to hepatocellul ar proliferative activity in altered liver acini.