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Updated: Aug 12, 2026
11:51
Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making
Published on: March 2, 2011
[Problems of dose finding: sexual hormones (author's transl)]
Arzneimittel-Forschung
|February 1, 1977
Summary
This study evaluates the predictive value of animal models for human steroid hormone activity, finding that some tests correlate well, while others, like oral rat tests for gestagens, are not relevant for human dose finding. Rabbit and rat models offer insights into gestagen and androgen activity duration, and estrogen depot effects.
Area of Science:
- Reproductive endocrinology
- Pharmacology
- Comparative physiology
Context:
- Species-specific regulation of reproductive processes necessitates careful evaluation of steroid hormone activity.
- The gestagen/estrogen ratio is critical for assessing gestagens, with some steroids exhibiting different activities (estrogenic vs. gestagenic) across species.
- Understanding species differences is crucial for extrapolating animal model data to human clinical applications.
Purpose:
- To assess the relevance and predictive value of various animal test models for evaluating the clinical efficacy and duration of action of gestagens, estrogens, and androgens.
- To identify reliable animal models for dose-finding and predicting depot effects of steroid hormones in humans.
- To investigate the correlation between peripheral and central activities of gestagens and the dissociation of anabolic and androgenic activities.
Summary:
- Significant correlations exist between gestagen activity in animal models and clinical trials, though oral rat tests are not predictive.
- Rabbit and rat models can inform conclusions about gestagen and androgen activity duration and depot effects in humans.
- Estrogenic activity in rats and mice correlates with antiovulatory activity, and the Allen-Doisy test aids in selecting depot estrogens.
Impact:
- Provides guidance on selecting appropriate animal models for steroid hormone research, improving the reliability of preclinical drug development.
- Highlights the limitations of certain animal tests (e.g., oral rat tests for gestagens) for human dose finding.
- Suggests that duration of activity in specific animal models (rabbits for gestagens, rats for androgens) can predict clinical depot effects.
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