Use of medaka (Oryzias latipes) as a model teleost to identify reproductive endpoints indicative of exposure to endocrine disrupting chemicals

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:244866

Papoulias, D M; Tillitt, D; Jones, S ^[1]; Noltie, D ^[2]

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1. National Biological Service, Columbia, MO (United States)
2. Univ. of Missouri, Columbia, MO (United States)

The purpose of this research is to identify effects of endocrine disrupting chemicals on the reproductive system of fish at various stages of sexual differentiation and development. The model teleost used was the d-rR strain of medaka (Oryzias latipes) which has a heritable sex-linked color gene. In medaka, sex differences are first detected at the cellular level at hatch. In males, the mitotic activity of the primordial germ cells (PGC) is arrested while the PGCs of the females continue to divide. The germ cells of the gonochoristic medaka have been demonstrated to be totipotent with respective to gonia production. Because endogenous sex steroid hormones are believed to regulate this early process of sexual differentiation, the authors have hypothesized that mitotic activity in males and females exposed to endocrine disrupting chemicals will be different than unexposed individuals. Results are presented for tests conducted by injecting medaka eggs within 36 hours post-hatch with 3 doses of 2,3,7,8-TCDD (nominally 2.3, 1.3, 0.2 pg/embryo), a known anti-estrogen, dissolved in triolein.

• OSTI ID: 244866
• Report Number(s): CONF-9511137--; ISBN 1-880611-03-1
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIOLOGICAL INDICATORS
DIOXIN
FISHES
REPRODUCTIVE DISORDERS
SEX DEPENDENCE
TOXICITY
WATER POLLUTION