Interactive effects of p,p'-dichlorodiphenyldichloroethylene and methoxychlor on hormone synthesis in largemouth bass ovarian cultures.
Environ Toxicol Chem
; 23(8): 1947-56, 2004 Aug.
Article
em En
| MEDLINE
| ID: mdl-15352484
ABSTRACT
p,p'-Dichlorodiphenyldichloroethylene (DDE) and methoxychlor were tested alone and in combination to assess the similarity of their actions on hormone synthesis in gonadal tissue from largemouth bass (Micropterus salmoides floridanus), a species whose reproductive fitness has relevance to ecosystem health in Florida (USA). Gonads were harvested from adult female bass (age, two to three years) during the peak reproductive season (January-May), minced, and incubated in culture medium with or without test agents for 48 h. Duplicates of each treatment were performed in each of three experiments using tissue from a different female. Both 17beta-estradiol and testosterone were measured in aliquots of culture medium by validated radioimmunoassay procedures. Dose-response relationships of individual agents were characterized over a 6-log concentration range (1 X 10(-2) to 1 X 10(4) ppb). Both DDE and methoxychlor, tested individually, produced a dose-dependent decrease in testosterone levels. 17beta-Estradiol levels were unaffected. Mixtures of the agents were tested at all concentration combinations of 0.01, 1, 100, and 10,000 ppb in culture medium. Statistical tests indicated that of 16 dose combinations tested, 15 were antagonistic, and only 1 was additive based on the Loewe additivity model of no interaction. These results imply that methoxychlor and DDE inhibit testosterone production by different mechanisms in bass ovaries.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ovário
/
Testosterona
/
Bass
/
Diclorodifenil Dicloroetileno
/
Estradiol
/
Inseticidas
/
Metoxicloro
Limite:
Animals
Idioma:
En
Revista:
Environ Toxicol Chem
Ano de publicação:
2004
Tipo de documento:
Article
País de afiliação:
Estados Unidos