Endocrinology, Vol 100, 187-196, Copyright © 1977 by Endocrine Society

ARTICLES

Estrogen formation by the ovary of the rabbit embryo

L Milewich, FW George and JD Wilson

The conversion of [1,2,6,7-3H]- testosterone to radioactive estradiol was assessed in tissue slices of 18 different tissues from rabbit embryos that varied in age from 16 to 29 days gestation. Significant rates of estradiol synthesis were demonstrated only in ovaries [4.2 +/- 0.7 (mean +/- SEM) pmol/h/mg) protein], placenta (0.7 +/- 0.2 pmol/h/mg protein) and brain (0.3 +/- 0.1 pmol/h/mg protein). Estradiol formation was undetectable in day 16 gonads of both sexes and in tests at all ages examined, but by day 18 it was demonstrable in ovaries and rose rapidly to reach a level of 6 pmol/h/mg protein by day 19. The time of appearance of the enzymatic capacity to convert testosterone to estradiol in the ovary is similar to the onset of the enzymatic capacity to form testosterone by the fetal testis, suggesting that the acquisition of the enzymatic activies that allow specific endocrine function by these two tissues may be regulated by the same or similar factors during embryonic development.

This article has been cited by other articles:

				M. Young and M. J. McPhaul A Steroidogenic Factor-1-Binding Site and Cyclic Adenosine 3',5'-Monophosphate Response Element-Like Elements Are Required for the Activity of the Rat Aromatase Promoter in Rat Leydig Tumor Cell Lines Endocrinology, December 1, 1998; 139(12): 5082 - 5093. [Abstract] [Full Text] [PDF]

				A Elbrecht and R. Smith Aromatase enzyme activity and sex determination in chickens Science, January 24, 1992; 255(5043): 467 - 470. [Abstract] [PDF]

				J. Wilson, F. George, and J. Griffin The hormonal control of sexual development Science, March 20, 1981; 211(4488): 1278 - 1284. [PDF]

				F. George and J. Wilson Estrogen formation in the early rabbit embryo Science, January 13, 1978; 199(4325): 200 - 201. [Abstract] [PDF]