| Abstract: | We investigated the influence of various kinds of glycosaminoglycans (GAGs) in collagen gels on the maintenance of albumin synthesis in primary culture of rat hepatocytes. Among the GAGs examined (heparin, heparan sulfate, keratan sulfate, chondroitin sulfate A, dermatan sulfate, and hyaluronic acid), only heparin-containing collagen gel cultures could significantly sustain albumin synthesis. However, other GAGs, such as heparan sulfate and keratan sulfate, had almost no effect on the maintenance of albumin synthesis. Heparin in collagen gels exhibited a dose-dependent effect on albumin synthesis: heparin at 400 μg/ml-collagen solution maintained albumin synthesis for over 3 weeks. On the other hand, when an equivalent amount of heparin was added directly to the collagen gel culture medium, it prolonged albumin synthesis for only 10 days. The results demonstrate that specific regulation of albumin synthesis by heparin was significantly promoted by coincubating it with collagen, suggesting that some specific interaction between heparin and collagen might be of importance for the maintenance of hepatocyte functions. |
