Nonylphenol Affects Gonadotropin Levels in the Pituitary Gland and Plasma of Female Rainbow Trout
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- 作者：Catherine A. Harris ; Eduarda M. Santos ; Afsaneh Janbakhsh ; Tom G. Pottinger ; Charles R. Tyler ; and John P. Sumpter
- 刊名：Environmental Science & Technology
- 出版年：2001
- 出版时间：July 15, 2001
- 年：2001
- 卷：35
- 期：14
- 页码：2909 - 2916
- 全文大小：385K
- 年卷期：v.35,no.14(July 15, 2001)
- ISSN：1520-5851
文摘
Female rainbow trout (Oncorhynchus mykiss) wereexposed to 4-nonylphenol (NP) at (mean measured)concentrations of 0.7, 8.3, and 85.6 
g/L, for 18 weeks,during early ovarian development. Fish were sampled sub-lethally every six weeks, and terminal samples weretaken at 18 weeks. NP induced an estrogenic effect (thesynthesis of vitellogenin) at concentrations of 8.3 and 85.6 g/L. An effect on gonadotropin synthesis and secretionwas also observed. Plasma follicle stimulating hormone(FSH) levels and FSH gene expression in the pituitary werethe most sensitive endpoints assessed, being reduced atthe lowest dose employed (0.7 gNP/L). Pituitary glandluteinizing hormone (LH) content was significantly lowerin fish exposed to 85.6 gNP/L, and LH gene expression wassuppressed in fish exposed to 8.3 and 85.6 gNP/L. Incontrast, plasma LH concentration increased in these fish,but by a very minor absolute amount, and returned tocontrol levels by the final sampling time. Gonadal developmentceased in the fish exposed to 85.6 gNP/L, and steroidogenesis in these fish was also markedly inhibited. Althoughthe mechanisms underlying these responses are unknown,this study demonstrates that NP has adverse effects onpituitary function that can result in inhibition of ovariandevelopment.
g/L, for 18 weeks,during early ovarian development. Fish were sampled sub-lethally every six weeks, and terminal samples weretaken at 18 weeks. NP induced an estrogenic effect (thesynthesis of vitellogenin) at concentrations of 8.3 and 85.6 g/L. An effect on gonadotropin synthesis and secretionwas also observed. Plasma follicle stimulating hormone(FSH) levels and FSH gene expression in the pituitary werethe most sensitive endpoints assessed, being reduced atthe lowest dose employed (0.7 gNP/L). Pituitary glandluteinizing hormone (LH) content was significantly lowerin fish exposed to 85.6 gNP/L, and LH gene expression wassuppressed in fish exposed to 8.3 and 85.6 gNP/L. Incontrast, plasma LH concentration increased in these fish,but by a very minor absolute amount, and returned tocontrol levels by the final sampling time. Gonadal developmentceased in the fish exposed to 85.6 gNP/L, and steroidogenesis in these fish was also markedly inhibited. Althoughthe mechanisms underlying these responses are unknown,this study demonstrates that NP has adverse effects onpituitary function that can result in inhibition of ovariandevelopment.