INFLUENCE OF THE FOETUS, PLACENTA AND OVARY ON THE MAMMOTROPHIC ACTIVITY OF PREGNANT RAT SERUM
- 1 November 1976
- journal article
- research article
- Published by Bioscientifica in Acta Endocrinologica
- Vol. 83 (3) , 640-650
- https://doi.org/10.1530/acta.0.0830640
Abstract
Serum mammotropic activity was assayed using an organ culture technique with histological endpoints. Using sera of 13 days pregnant rats with 1-18 conceptuses, activity was detectable even in the presence of 1 conceptus, but the activity with 1-4 conceptus(es) tended to be less than with 6-18. Serum of rats with 1-3 conceptus(es) was approximately 2-4 times less active than serum of rats with 14 conceptuses. Removal of the conceptuses on day 15 caused loss of mammotropic activity of the serum, tested 4 days later. When the fetuses, the ovaries or both the fetuses and ovaries were removed on day 15 of pregnancy, mammotrophic activity was present in the serum collected 4 days later. Differences in activity between the treated groups were small. Mammotropic activity was comparable to the activity of serum of untreated 15 days pregnant rats or 19 days sham-operated pregnant rats. Explanted single fragments of a 19 days pregnant rat placenta released activity into the medium. The placenta retained this capacity even when the fetus had been removed 4 days previously.This publication has 1 reference indexed in Scilit:
- MAMMOTROPHIC ACTIVITY IN RAT SERUM DURING THE OESTROUS CYCLE, PREGNANCY AND LACTATIONActa Endocrinologica, 1976