抄録
We have previously demonstrated that only when serum was included in the culture medium, heparin-binding fibroblast growth factor-1 (FGF-1) was a potent mitogen for rat hepatocytes in primary culture. Here we have defined the constituents of serum that is important for the mitogenic activity of FGF-1. Addition of dialyzed serum to the basal medium supported about half of the FGF-1 activity compaired to whole fetal bovine serum (FBS). Further addition of ascorbic acid 2-phosphate to this medium reconstituted the full activity of FGF-1. However, ascorbic acid 2-phosphate alone could only partially support the FGF-1 mitogenicity. These findings indicate that dialyzed-FBS and ascorbic acid 2-phosphate additively or synergistically support the mitogenic activity of FGF-1. These effects of dialyzed FBS and ascorbic acid 2-phosphate were observed regardless of the basal medium used, i. e., Williams'medium E or MCDB 107 medium. Thus, these results suggest that the high molecular-weight factor(s) and ascorbic acid-like compound(s) are the important constituents of serum that support the FGF-1 mitogenic activity.
