Influence of 20α-Dihydroprogesterone on Progesterone Output by Human Chorion Explants
Bibliographic record
Abstract
The output of progesterone by explants of chorion incubated without exogenous precursor was increased in the presence of 20 alpha-dihydroprogesterone (20 alpha-diHP). We have now examined the nature of the 20 alpha-diHP effect. Explants of chorion were incubated with [3H]progesterone and 3 microM non-radiolabelled 20 alpha-diHP to examine the effect of 20 alpha-diHP on progesterone metabolism. Significantly more radioactivity remained as unmetabolized [3H]progesterone compared to chorion incubated in the absence of non-radiolabelled 20 alpha-diHP. There was also a decrease in the output of [3H]-20 alpha-diHP by the explants but no change in the output of a second metabolite of progesterone [3H]-5 alpha-pregnanedione. When explants were incubated with 20 alpha-diHP in the presence of the 3 beta-hydroxysteroid dehydrogenase inhibitor, trilostane, the output of progesterone was significantly greater than with explants incubated with trilostane but without addition of 20 alpha-diHP. Radiochemically pure [3H]progesterone was produced by explants of chorion incubated with [3H]-20 alpha-diHP. We conclude that 20 alpha-diHP may serve as substrate for chorionic progesterone production through 20 alpha-hydroxysteroid dehydrogenase. 20 alpha-diHP, formed from progesterone, may also exert product feedback inhibition on this enzyme.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".