ANTAGONISTIC EFFECT OF DEXAMETHASONE AND INSULIN ON ALPHA-FETOPROTEIN SECRETION BY CULTURED H4-II-E-C3 CELLS DERIVED FROM THE REUBER H-35 HEPATOMA

Non-confluent monolayers of H4-II-E-C3 cells were maintained in serum-free media. Dexamethasone alone (5 × 10-7M) stimulated α-fetoprotein secretion 2- to 4-fold while insulin alone (8.7 × 10-8M) inhibited α-fetoprotein secretion by 20%. When dexamethasone (5 × 10-7 to 5 × 10-9M) and insulin (8.7 × 10-8 to 8.7 × 10-11M) were added simultaneously, insulin diminished the stimulatory effect of dexamethasone. When α-fetoprotein secretion was elevated by dexamethasone and the medium was replaced by media containing either insulin or no hormones, the rate of α-fetoprotein secretion diminished more rapidly with the insulin-supplemented medium. Alone or in combination, insulin and dexamethasone had little effect on albumin secretion. © 1979.