ROSEN, G.*; WADE, J.: Androgen metabolism in the green anole lizard brain 5ALPHA-reductase facilitates male courtship behavior in green anole lizards by converting testosterone (T) to dihydrotestosterone. The present study was done to determine whether sex and seasonal differences in the enzyme’s activity occur in the anole brain, reflecting its role in male courtship behavior. […]

GRINDSTAFF, R.D.*; PYLES, R.A.: Thyroid and prolactin hormones in metamorphic and paedomorphic species of ambystomatid salamanders The endocrine control of metamorphosis, long identified with circulating levels of thyroid hormone and prolactin, has been studied almost exclusively in anurans with little research on hormonal control of metamorphosis among urodeles. Comparisons of hormone levels in metamorphic and […]

McNABB, F.M.A.*; FOWLER, L.A.; PARSONS, C.M.; GRASMAN, K.A.; FOX, G.A.: Thyroid Function in Herring Gulls from PCB-contaminated Great Lakes sites. We have investigated thyroid function in pipped embryos and prefledglings of herring gulls sampled in 1998 and 1999 at several Great Lakes sites with different amounts of PCB contamination and have compared them with gulls […]

MCCLEARY, R.J.R.*; MCFARLAND, E.C.; GRASMAN, K.A.; MCNABB, F.M.A.: Ontogeny of UDP-GT activity in Japanese quail and effects of PCB 126 on UDP-GT activity in chicken embryos. Uridinediphosphate-glucuronosyltransferases (UDP-GTs) are important phase II liver biotransformation enzymes responsible for conjugation of many endogenous and exogenous substances in vertebrates. Induction of UDP-GTs has been shown in birds exposed […]

COSTANTIO,D.*; KOZAK, K.; LECAUDE, S.; ALRUBAIAN, J.; DORES, R.M.: Cloning of a proopiomelanocortin cDNA from the pituitary of the urodele amphibian, Aphiuma means. The proopiomelanocortin (POMC) gene has been cloned from several anuran amphibians, however, the organization of this prohormone-coding gene had not been analyzed in a urodele amphibian. A degenerate primer was used to […]

MANZON, L.A.*; LAUDET, V.; YOUSON, J.H.: Cloning and Expression of Sea Lamprey (Petromyzon marinus) Thyroid Hormone and Retinoid X Receptors. Sea lampreys (Petromyzon marinus) are extant representatives of an ancient group of vertebrates with a history that can be traced over 500 million years. A dramatic decline in serum thyroid hormones (TH) occurs at the […]

McGinn, N.A.*; Walker, C.W.: Vitellogenesis in the green sea urchin, Strongylocentrotus droebachiensis: Localization of vitellogenin protein in gonadal tissue The green sea urchin, Strongylocentrotus droebachiensis, is the focus of a commercial fishery and an aquaculture candidate. It is therefore imperative that we understand the general and reproductive biology of this species. In particular, vitellogenesis is […]

Pak, T.R.*; Lynch, G.R.; Tsai, P.-S.: TESTOSTERONE AND ESTROGEN ACT VIA DIFFERENT PATHWAYS TO INHIBIT PUBERTY IN MALE SIBERIAN HAMSTERS Testosterone (T), dihydrotestosterone (DHT), and 17b-estradiol (E) induce testicular regression in peripubertal, male, Siberian hamsters, Phodopus sungorus. Since T can be converted to DHT or E, whether T acts directly or through its metabolites to […]

MAYER, L.P* and; DYER, C. A.; PROPPER, C. R.: Sexual dimorphism in gonadal steroidogenic factor 1 (SF-1) expression during sexual differentiation and the effects of octylphenol on the differentiation process in the American bullfrog Rana catesbeiana. Gonadal steroidogenesis during development is critical to differentiation of the adult sexually dimorphic phenotype and reproductive function. Environmental contaminants […]

Howdeshell, K.L.*; Ruhlen, R.L.; Welshons, W.V.; vom Saal, F.S.: Serum regulation of estrogenic endocrine-disrupting chemicals during mouse neonatal development Certain chemicals used in plastics and other products are capable of disrupting development by mimicking the action of the sex hormone estradiol, and thus are referred to as estrogenic endocrine disrupting chemicals (EEDCs). While traditional risk […]