BIOLOGIA, sa.3, ss.375-382, 2004 (SCI-Expanded)
Adult mammalian liver cells multiply rapidly and enable regeneration of the organ following damage or partial hepatectomy (PH). Previously, we observed that implantation of Ehrlich ascites tumor (EAT) cells to mice immediately after 35% hepatectomy caused an increase in liver regeneration and labeling index. Growth of the EAT cells in mice is characterized by an initial exponential phase followed by a plateau phase 9-10 days after inoculation. It is also known that the ascitic fluid, formed during the growth of tumor, affects the multiplication of the cells so regenerative growth of the liver can have a selective effect on tumor growth. The main aim of the present study was to investigate how these two types of growth (regenerative and tumoral) could affect each other. In this study the liver regeneration percentage and multiplication of tumor cells on different days of mice (Mus musculus), to which 3 x 10(6) EAT cells were implanted immediately after the application of 57% PH, were investigated. According to the results obtained from the experiments, it is suggested that the stimulating effect on regeneration percentage of tumor seen originated either from only EAT tumor or from a synergistic impact of tumor together with stimulatory factors in regenerative growth. However, as a result of the presence of agents, such as PH ratio, tumor's variety, Immoral factor and human hepatocyte growth factor from growth factors, singly or more than one together, regenerative growth stimulates the multiplication of EAT cells in the same host.