[Transplantation of isolated hepatocytes into the spleen of rats]

The effects of splenic transplantation of hepatocytes on survival time and hepatic regeneration were studied in adult rats subjected to: 1) 90% hepatectomy plus portocaval shunt (graft of 4 x 10(6) hepatocytes) and 2) 90% hepatectomy (graft of 4 x 10(6) and 8 x 10(6) hepatocytes); data were compared with those obtained in hepatectomized rats. Hepatic regeneration was significantly higher in transplanted rats and, within animals with grafted hepatocytes more pronounced in rats without porto-caval shunt. This support the hypothesis that a hepatotrophic factor is produced by grafted hepatocytes: its activity is more pronounced in the absence of porto-caval shunt since all splenic blood reach the liver. The activity of the putative hepatocyte growth factor does not depend on the number of grafted hepatocytes since no significant differences in survival time and hepatic regeneration was observed between rats grafted with 4 x 10(6) and 8 x 10(6) hepatocytes.