Effect of two forms of granulocyte-colony-stimulating factor on hepatic regeneration after 70% partial hepatectomy in rats.

1. The purpose of this study was to determine whether the commercially available forms of granulocyte-colony-stimulating factor exert the same beneficial effect on hepatic regeneration after 70% partial hepatectomy in rats. Adult male Wistar rats received either the two commercially available forms of granulocyte-colony-stimulating factor (Filgrastim or Lenograstim), or saline, simultaneously with partial hepatectomy. Hepatic regeneration was documented by determining [3H]thymidine incorporation into hepatic DNA, liver thymidine kinase activity, mitotic index and proliferating cell nuclear antigen immunostaining, at various time points after partial hepatectomy. 2. DNA biosynthesis, liver thymidine kinase activity and mitotic index of hepatocytes were not only enhanced (P < 0.001) in rats that received 150 micrograms of Filgrastim or Lenograstim/kg of body weight, but occurred earlier than in saline-treated partially hepatectomized rats. The administration of both forms of granulocyte-colony-stimulating factor, at the dose of 15 micrograms/kg of body weight, did not affect liver proliferative capacity, compared with observations in simply partially hepatectomized rats. High mitotic and proliferating cell nuclear antigen indices appeared earlier than those estimated in simply partially hepatectomized rats, when 150 micrograms of Filgrastim or Lenograstim/kg of body weight were administered. 3. These findings suggest that both pharmacologically available forms of granulocyte-colony-stimulating factor at a dose of 150 micrograms/kg of body weight are able to augment liver regenerative capacity, to the same extent, in this animal model of controlled hepatic proliferation.