1. Receptor Biology Section/Laboratory of Reproductive and Developmental Toxicology (W.P.B., S.C.H., K.S.K.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709
2. The Department of Biology (J.K.L.), University of South Florida, Tampa, Florida 33620
3. Comparative Medicine Branch (J.A.C., P.H.M.), National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709
4. Reproductive Toxicology Division (R.C.), Environmental Protection Agency, Research Triangle Park, North Carolina 27711