This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by TSENG, L. Search for Related Content PubMed PubMed Citation Articles by TSENG, L.

Steroid Specificity in the Stimulation of Human Endometrial Estradiol Dehydrogenase^*

LINDA TSENG

Department of Obstetrics and Gynecology, School of Medicine, Health Sciences Center, State University of New York of Stony Brook Stony Brook, New York 11994
Mount Sinai School of Medicine, City University of New York New York, New York 10029

Abstract

Progesterone (P) stimulates estradiol dehydrogenase (E₂DH) activity in human proliferative endometrium. The potencies of several progestins were studied in this system. Endometrium was incubated for 2–3 days in a culture medium containing various concentrations of steroids. The E₂DH activity was measured at the end of the incubation. Steroid specificity was studied by examining the dose-response characteristics for each progestin in the stimulation of the enzyme activity. In this system, the most potent progestins, medroxyprogesterone acetate, R-5020, and P, were able to stimulate endometrial E₂DH at a concentration as low as 3 nM after 2 days of incubation. 17-Hydroxyprogesterone (17-OHP) caproate was effective at 30 nM, whereas high concentrations (>100 nM) of medroxyprogesterone and 17-OHP were required in order to produce a detectable increase in activity. All of these compounds, except 17-OHP, produced a dose-dependent increase in E₂DH activity. Based on the relative stimulation observed, it appears that a hydroxyl group, especially at the 17 position, greatly reduces the ability of a progestin to stimulate the enzyme. However, this capacity is restored by esterification of the hydroxyl group. In addition, corticosterone (B), but not cortisol, was found to be able to increase E₂DH activity. However, the doseresponse curve was entirely different from that of the progestins. At least 200 nM B was required before an increase in enzyme activity could be detected. Kinetic analysis of the stimulation of E₂DH revealed that the maximum enzyme activity stimulated was similar when using either P or B. However, the concentrations required to reach the half-maximum enzyme activity were very different (10 nM for P and 1400 nM for B). These results suggest that B may not be physiologically significant as a stimulator. (Endocrinology 102: 1398, 1978)

Footnotes

^* This work was supported by Grant HD 07197 and HD 10933 from the NIH and Grant HRC 612 from the NY State Health Research Council.

Present address: Department of Obstetrics and Gynecology, School of Medicine, Health Sciences Center, State University of New York at Stony Brook, Stony Brook, New York 11794. To whom requests for reprints should be addressed.

Received May 19, 1977.

This article has been cited by other articles:

				P. Satyaswaroop, R. Zaino, and R Mortel Human endometrial adenocarcinoma transplanted into nude mice: growth regulation by estradiol Science, January 7, 1983; 219(4580): 58 - 60. [Abstract] [PDF]