[Regulation of the cultured mouse parenchymal liver cells (P-LC) by mast cells]

Mast cells suppressed the proliferation of parenchymal liver cells (P-LC) in a dose-dependent manner, when they were cocultured with P-LC. On the contrary, mast cells activated by IgE and anti-IgE enhanced DNA synthesis of P-LC dose-dependently. The activity enhancing the proliferation of P-LC was found in the supernatant of the activated mast cells, but not in that of untreated mast cells, suggesting the secretion of active factors by active mast cells. Histamine, which are released by the activated mast cells, suppressed the enhancement of P-LC proliferation by activated mast cells. Since histamine and heparin did not effect the proliferation of P-LC directly, histamine may bring the suppression through regulating the activated mast cell. On the basis of these findings, we discuss the role of mast cells in liver regeneration.