Synthesis in Vitro of Glycosaminoglycans in Regenerating Rat Liver

Summary: Chronic liver damage is accompanied by both liver cell multiplication and stimulated synthesis of proteo-glycans, but the relationship between the two biochemical processes has not been investigated so far. We found that the incorporation of [14C]glucosamine into total glycosaminoglycans of rat liver slices from regenerating tissue is depressed by about 50 % 1 and 3 days after operation if referred to that measured in sham-operated control liver slices. 6 h after partial hepatectomy [l4C]glucosamine incorporation into glycosaminoglycans is stimulated by more than 30 % in relation to sham operated livers. The proportional rates of synthesis of heparan sulfate and chondroitin sulfate (about 8:1) did not change in regenerating liver tissue. Furthermore, there was no difference in the intracellular uptake of [14C]glucosamine by rat liver slices from sham operated and partially hepatectomized rats; the pool size of UDP-N-acetylhexosamine was only slightly larger (about 14%) under the latter experimental condition. We conclude that liver regeneration by itself is not responsible for the elevated production and the changing pattern of proteo-glycans in long-lasting hepatic injury. Die in vitro Biosynthese der Glykosaminoglykane in der regenerierenden Rattenleber Zusammenfassung: Chronische Leberschädigungen werden begleitet sowohl von Leberzellregeneration als auch stimu