Hepatocyte growth factor up-regulates met expression in rat fetal hepatocytes in primary culture.

Hepatocyte growth factor (HGF) is a potent mitogen for primary cultured fetal hepatocytes. In the present study, we have analyzed the c-met/HGF receptor expression in fetal hepatocytes and its modulation by growth factors and hormones. 20-day old fetal liver showed a barely expression of c-met mRNA levels. However, when fetal hepatocytes were incubated in the presence of HGF, a 10-fold increase in c-met mRNA levels was observed 30 min after addition of the factor. This HGF-induced effect on c-met expression was transient, losing its up-regulatory effect after 24 hours and returning to the initial levels at 48 hours. Transforming growth factor-beta, a negative regulator of fetal liver growth, increased c-met mRNA levels 48 hours after the addition of the factor, whereas glucocorticoids had a negative effect.