Application of zebrafish in toxicity testing

The zebrafish or Danio rerio originated in India. It is a small tropical fish with a chromosome number of 50 and an adult length of 3 to 4 cm. It reaches sexual maturity within about 3 months after hatching. Mature females can produce several hundred eggs every other week. Oocytes were fertilized in vitro, developed in vitro, and their embryonic development was synchronous. The growth rate was fast and was correctly developed between 25 and 31°C. The zebrafish is the most commonly used laboratory animal for standard toxicological testing and it is also recommended by the ISO for river toxicity testing.
Zebrafish as an ISO Standard for Experimental Fish:
ISO7346-1: Water quality — Determination of the acute lethal toxicity of substances to a fresh water fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae)] — Semi-static method
ISO7346-2: Water quality — Determination of the acute lethal toxicity of substances to a fresh water fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae)] — Static method
ISO7346-3: Water quality — Determination of the acute lethal toxicity of substances to a fresh water fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae)] — Flow-through method
The above criteria apply to the detection of zebrafish for reproduction, feeding and maintenance of water hardness, pH, water temperature, zebrafish inducing oviposition method, spawning temperature, food feeding during oviposition, egg and seedling protection method, adult fish Feeding time and feed, and fry feeding methods have been detailed.
The zebrafish has been listed as an experimental standard fish by the Organisation for Economic Cooperation and Development (http://www.economy-development-organisation.org), used for the evaluation of the hazards of acetic acid and potassium chloride, a-dichlorotoluene and 11-amino-11. Acute acid toxicity test.
Domestic use of zebrafish to detect water quality applications:
In 2001, the Shanghai Environmental Monitoring Center collected water samples from several sections of Zhaotun, Qingpu, etc., and used zebrafish for acute river toxicity tests. The test results showed that the river water taken from the mainstream of the Suzhou River did not reach the concentration of 50% of the fish that was lethal in the acute toxicity test (Shanghai Normalization. 2001(5).-24-24).
Application of transgenic zebrafish in the detection of water pollutants:
At the Cincinnati Medical Center in the United States, transgenic zebrafish, whose reporter gene is controlled by three response elements, were constructed to monitor pollutants in the water. The three response elements are (1) Aromatic Responsive Element, which responds to many polycyclic hydrocarbons, halogenated coplanar molecules such as dioxins and PCBs; (2) electrophilic response elements, which can be benzene醌 and many other potential electrophilic oxidants respond; (3) Metal-responsive elements that respond to heavy metal ions such as mercury, copper, nickel, cadmium, and zinc (Ann NY Acad Sci. 2000, 19:133-47) ).
The National University of Singapore has successfully established two types of transgenic zebrafish: estrogen-induced activation control of fluorescent gene expression and stress response control initiates the control of fluorescent gene expression. In the presence of estrogen-like substances, zebrafish containing estrogen-inducible promoters that control the expression of fluorescent genes emit color fluorescence; in the presence of heavy metals and toxicants, the zebrafish that controls the expression of fluorescent genes with stress response initiates color fluorescence. .
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Using the “transgenic zebrafish” as a search strategy, a total of two patents for detecting pollutants in water using transgenic zebrafish were retrieved:
The World Patent WO0049150 filed by National University of Singapore on July 7, 1999 discloses the use of steroid hormones to induce the control of fluorescent protein-expressing transgenic zebrafish to monitor steroid hormones and steroid hormone analogues in aquatic environments; The transgenic zebrafish monitors the heavy metals zinc, copper, cadmium, and mercury in the aquatic environment.
U.S. Patent No. 2004147030 filed on July 7, 2004 by NEBERT DANIEL W discloses that a transgenic zebrafish controlled by a contaminant-induced response element of a reporter gene is used to detect the concentration of a contaminant by detecting the intensity of the fluorescence using a fluorescence detector and luciferin. The contaminant-induced response elements include metal-responsive elements, aromatic hydrocarbon-responsive elements, estrogen-responsive elements, electrophilic-responsive elements, and retinoic acid-responsive elements.

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