Bovine Fetal Pituitary Concentration and In Vitro Synthesis of Prolactin,GH,and LH 1

Abstract

Summary

Luteinizing hormone, GH, and prolactin were quantified by radioimmunoassay in 34 fetal bovine pituitaries. Pituitary LH concentration increased with fetal age from 323 to 474, and to 535 ng/mg at 90, 180, and 260 days, respectively. Pituitaries cultured in vitro synthesized significant quantities of LH. Differences in LH synthesis due to sex or age of pituitary donor were not significant. Fetal pituitary GH increased during gestation (4.2, 8.9, and 18.1 μg/mg at 90, 180, and 260 days, respectively). GH for male and female fetuses was similar at 90 and 180 days, but pituitaries from males contained less GH (12.1 μg/mg) than females (25.3 μg/mg) at 260 days. Growth hormone was not synthesized in vitro in significant quantities. Fetal pituitaries contained increasing quantities of prolactin (72, 1150, and 2508 ng/mg for 90, 180, and 260 days, respectively) with advancing fetal age, and synthesized in vitro more prolactin than LH. Pituitaries from female fetuses synthesized three times more prolactin than males at 180 and 260 days.