In vitro growth of adult amphibian (Xenopus laevis) hepatocytes and characterization of hepatocyte-proliferating activity in homologous serum.
Adult frog (Xenopus laevis) hepatocytes were found to proliferate in a culture medium containing adult homologous serum. Insulin and dexamethasone were required for a net proliferation of hepatocytes. Dose-response analysis showed that a low concentration of serum (greater than or equal to 0.5%) was enough to induce DNA synthesis and mitosis, but a higher concentration (5%) caused certain necrotic changes. Under optimal conditions, there was a two- to threefold increase in nuclei per culture 10 days after serum treatment. Heterologous sera (fetal bovine, calf and chick) showed less proliferative activity. Based on our results, hepatocyte-proliferating activity in adult frog serum is considered to be heat-unstable and acidic protein(s). Thus, adult frog serum may contain hepatopoietin possibly different from well-known growth factors.
D000818:Animals; D002455:Cell Division; D002478:Cells, Cultured; D003907:Dexamethasone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D007328:Insulin / Q000494:pharmacology; D015850:Interleukin-6; D008099:Liver / Q000166:cytology*; D011506:Proteins / Q000032:analysis*; D014982:Xenopus laevis / Q000378:metabolism*
D007328:Insulin; D015850:Interleukin-6; D011506:Proteins; D003907:Dexamethasone