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The OECD Program to Validate the Rat Hershberger Bioassay to Screen Compounds for in Vivo Androgen and Antiandrogen Responses: Phase 2 Dose–Response Studies
| Content Provider | Semantic Scholar |
|---|---|
| Author | Owens, William Gray, Leon Earl Zeiger, Errol Walker, Michael Yamasaki, Kanji Jacob, Elard |
| Copyright Year | 2007 |
| Abstract | OBJECTIVE The Organisation for Economic Co-operation and Development (OECD) has completed phase 2 of an international program to validate the rodent Hershberger bioassay. DESIGN The Hershberger bioassay is designed to identify suspected androgens and antiandrogens based on changes in the weights of five androgen-responsive tissues (ventral prostate, paired seminal vesicles and coagulating glands, the levator ani and bulbocavernosus muscles, the glans penis, and paired Cowper's or bulbourethral glands). Protocol sensitivity and reproducibility were tested using two androgen agonists (17alpha-methyl testosterone and 17beta-trenbolone), four antagonists [procymi-done, vinclozolin, linuron, and 1,1-dichoro-2,2-bis-(p-chlorophenyl)ethylene (p,p'-DDE)], and a 5alpha-reductase inhibitor (finasteride). Sixteen laboratories from seven countries participated in phase 2. RESULTS In 40 of 41 studies, the laboratories successfully detected substance-related weight changes in one or more tissues. The one exception was with the weakest antiandrogen, linuron, in a laboratory with reduced sensitivity because of high coefficients of variation in all tissue weights. The protocols performed well under different experimental conditions (e.g., strain, diet, housing protocol, bedding, vehicle). There was good agreement and reproducibility among laboratories with regard to the lowest dose inducing significant effects on tissue weights. CONCLUSIONS The results show that the OECD Hershberger bioassay protocol is reproducible and transferable across laboratories with androgen agonists, weak androgen antagonists, and a 5alpha-reductase inhibitor. The next validation phase will employ coded test substances, including positive substances and negative substances having no androgenic or antiandrogenic activity. |
| Starting Page | 671 |
| Ending Page | 678 |
| Page Count | 8 |
| File Format | PDF HTM / HTML |
| PubMed reference number | 17520051v1 |
| Volume Number | 115 |
| Journal | Environmental health perspectives |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | 1,1-bis(4-chlorophenyl)ethylene oxide Androgen Antagonists Androgens Bacteria identified:Prid:Pt:VP shunt:Nom:Culture Beds Biological Assay Body tissue Bulbourethral gland structure Dichlorodiphenyl Dichloroethylene Finasteride Glans penis Laboratory Linuron Lobular Neoplasia Mandatory - HL7DefinedRoseProperty Organisation for Economic Co-Operation and Development Protocols documentation Seminal Vesicles Structure of bulbospongiosus muscle Structure of levator ani muscle Testosterone Vesicle (morphologic abnormality) Vulval intraepithelial neoplasia Weight vinclozolin |
| Content Type | Text |
| Resource Type | Article |
