Effects of exposure to 17α-ethinylestradiol during early development on sexual differentiation and induction of vitellogenin in zebrafish (Danio rerio)

Probing the xeno-oestrogenic impact of sediment cores contaminated by the pulp and paper industry: induction of aromatase cyp19a1b in late larval zebrafish

“…Among other small-bodied species, such as the fathead minnow Pimephales promelas (Panter et al 2000, Johns et al 2011 and Japanese medaka Oryzias latipes (Melo andRamsdell 2001, Han et al 2010), it is routinely used for basic and applied endocrine studies of chemicals used in the environment and environmental samples. With the flexibility of assessment endpoints, life-stages of zebrafish from post-fertilized egg through embryonic, juvenile up to adult animals have been widely used to study developmental (Kimmel et al 1995), mutational (Incardona et al 2004), teratogenic (Brannen et al 2010) and reproductive (Andersen et al 2003, Van den Belt et al 2003, Segner et al 2003 impacts among other toxicity investigations. Specifically, endocrine status has also been widely studied in zebrafish ELS , Andersen et al 2003, Brion et al 2004, Kazeto et al 2004, Muncke and Eggen 2006.…”

“…With the flexibility of assessment endpoints, life-stages of zebrafish from post-fertilized egg through embryonic, juvenile up to adult animals have been widely used to study developmental (Kimmel et al 1995), mutational (Incardona et al 2004), teratogenic (Brannen et al 2010) and reproductive (Andersen et al 2003, Van den Belt et al 2003, Segner et al 2003 impacts among other toxicity investigations. Specifically, endocrine status has also been widely studied in zebrafish ELS , Andersen et al 2003, Brion et al 2004, Kazeto et al 2004, Muncke and Eggen 2006. Progress in existing in vivo screening of vertebrate gene function has seen the increased use of transgenic and morpholino antisense oligos or gene knockdown technologies (Carvan et al 2005, Hill et al 2005, Hahn and Hestermann 2008, and in particular the induction of green fluorescent protein expression in transgenic zebrafish, cyp19a1b-GFP , Brion et al 2012 and ere-zvtg1: gfp , presenting non-lethal alternatives in animal testing.…”

“…Yolk, besides being the energy and maternal source until the free-feeding stage of the developing fry, is also the route of exposure to lipophilic toxicants transferred from the mother fish. Secondly, whereas the presence of chorion encapsulating the embryo is a barrier to unrestricted chemical exposure (Lillicrap 2010, Henn andBraubeck 2011), the yolk sac of eleutheroembryos acts as a sink for lipophilic chemicals (Andersen et al 2003). For instance, structural composition of the zebrafish embryo at the gastrula stage (7 hpf) includes a three-layered chorion enveloping yolk at the core surrounded by a syncytial layer and perivitelline space (Rawson et al 2000).…”

“…Subsequent responses include the physiological production of proteins (Vtg) over long-term exposures. The half-life of vitellogenin protein, being 2.4 d in juvenile zebrafish exposed from 0-25 dph to 15 ng EE2 l -1 (Andersen et al 2003), is an important information, along with higher stability of Vtg mRNA relative to the protein level (Muncke et al 2007). However, vitellogenin protein half-lives in some cold water species, such as flounder (15 d) and plaice (35 d), were significantly longer than the respective half-lives of mRNA, at 2.8 and 3.1 days respectively (Craft et al 2004).…”

Effects of Different Hormones on Sex Reversal of Rainbow Trout (Oncorhynchus MykissWalbaum) and Production of All-Female Populations

“…17α-Metiltesteron and estradiol-17β are the most widely used hormones. Individuals especially of Cichlidae and Cyprinidae may grow 2-3 times faster when they are treated with optimal hormone dosage (1,9,18). …”