| Abstract: | The effects of several hormones on total RNA and protein biosynthesis were examined in primary cultures of liver cells obtained from rat fetuses on 21-22 days of gestation and from 3 week-old weanling rats. The intensity of biosynthesis processes was estimated by the incorporation of labeled precursors in macromolecules. Insulin, cortisol, triiodothyronine (T3) stimulated RNA and protein biosynthesis in both types of cultures. These hormones enhanced total protein biosynthesis in fetal rat liver cells more efficiently than in hepatocytes of weanling rats. Somatotropin (growth hormone--GH) did not change total protein biosynthesis but notably increased RNA synthesis and the production of immunoreactive serum albumin. Experiments on fetal rat liver cell cultures showed that stimulating action of cortisol on RNA synthesis was synergistic in relation to the effects of insulin and GH. It has been concluded that fetal rat liver cell at the end gestation are able to respond adequately to anabolic action of the hormones. |
