DOSE-RESPONSE KINETICS OF SERUM VITELLOGENIN, LIVER DNA, RNA, PROTEIN AND LIPID AFTER INDUCTION BY ESTRADIOL-17-BETA IN MALE FLOUNDERS (PLATICHTHYS-FLESUS L)

1. 1. Male flounders receiving 100 μg estradiol each second day were fully induced to vitellogenin synthesis within 11 days, while fishes given 5μg doses continued to accumulate vitellogenin in the serum at a progressive rate through 17 days. 2. 2. Liver DNA per unit fish remained constant, while RNA per unit fish in flounders given 100 and 5 μg doses attained values 80 and 25%, respectively, above the values found in control animals. 3. 3. Liver RNA per unit DNA increased at maximal rate within 6 days in fishes receiving 100 μg doses. RNA synthesis continued at a progressive rate through 17 days in fishes given 5 μg doses of estradiol. 4. 4. Liver protein per unit DNA elevated at a plateau 60% above control within 6 days with 100 μg doses. Doses of 5 μg had only little effect on liver protein. 5. 5. Estradiol had a lipogenic effect on the liver. Cellular lipid rose 120 and 60% above control after treatment with 100 and 5 μg respectively. 6. 6. Liver dry weight per unit DNA increased 60 and 55% above control with 100 and 5 μg doses respectively. Cellular hypertrophy in fishes receiving the smaller dose was primarily associated with an increase in lipid concentration, while protein and lipid contributed almost equally to cellular growth in fishes receiving the high dose. © 1979.