Survival rates of <i>Tg(nkx2.2a:mEGFP)</i> fry in the presence of different concentrations of testing chemicals.

<p>Survival rates at 8, 24, 48 and 96 hpf were plotted against different concentrations of the chemicals. Chemical names are indicated above each panel.</p

Body length, CNS length and axon length of <i>Tg(nkx2.2a:mEGFP)</i> fry in the presence of variable chemicals.

<p>(A–C) Examples of measurements of body length (A), CNS length (B) and axon length (C). The measured lengths are indicated by double arrow lines. Scale bars: 1000 µm in (A.B) and 100 µm in (C). (D) Histograms of body length, CNS length and axon length. Chemical names and concentrations are indicated on the left. Statistical significance: **P<0.01; *P<0.05.</p

Examples of abnormal phenotypes.

<p>(A, D) Normal developing control embyors/fry in o.01% DMSO at 24 hpf (A) and 72 hpf (D); (B) No tail detachment at 24 hpf in 20 mg/L acetaminophen; (C) No somite at 24 hpf in 25 mg/L acetaminophen; (E) Edema at 72 hpf in 20 mg/L lindane; (F) Light pigmentation at 72 hpf in 250 µg/L mefenamic acid; (G) No hatching at 72 hpf in 10 mg/L lindane; (H) Coiled body at 96 hpf in 5 mg/L lindane. Scale bars: 200 µm.</p

Lowest effective concentrations of neurotoxins for shortening of motoneuron axons.

<p>Lowest effective concentrations of neurotoxins for shortening of motoneuron axons.</p

Summary of selected DarT endpoint measurements.

<p>(A) Hatching (96 hpf), (B) Heartbeat (48 hpf), (C, D) Tail detachment (24 hpf, 48 hpf), (E, F) Normal somite (24 hpf, 48 hpf). Names and concentrations of chemicals are indicated at the bottom of Panel F. 0.01% DMSO was used as control except that egg water was used as control for ethanol test. Hearbeat is shown as numbers per 15-second. Statistical significance: **P<0.01; *P<0.05.</p

General phenotypes (left row), GFP-expressing central nervous systems (middle row) and motoneuron axons (right row) of 80-hpf <i>Tg(nkx2.2a:mEGFP)</i> fry in the presence of effective concentrations of different chemicals.

<p>(A) 0.01% DMSO control, (B) 5 mg/L Acetaminophen, (C) 2.5 mg/L Atenolol, (D) 2 mg/L Atrazine, (E) 0.5% Ethanol, (F) 1.25 mg/L Lindane and (G) 250 µg/L Mefenamic acid. Somite numbers are indicated at the top right panel. Scale bars: 1000 µm for the left and middle rows and 100 µm for the right row.</p

Comparison of the mRNA levels of endogenous <i>fabp10a</i> and transgenic DsRed in LiPan fry treated with variable chemicals.

<p>Quantification was carried out by RT-qPCR. Bule bars represent <i>fabp10a</i> mRNA and red bars refer <i>DsRed</i> mRNA.</p

Development of a Convenient <i>In Vivo</i> Hepatotoxin Assay Using a Transgenic Zebrafish Line with Liver-Specific DsRed Expression

<div><p>Previously we have developed a transgenic zebrafish line (LiPan) with liver-specific red fluorescent protein (DsRed) expression under the <i>fabp10a</i> promoter. Since red fluorescence in the liver greatly facilitates the observation of liver in live LiPan fry, we envision that the LiPan zebrafish may provide a useful tool in analyses of hepatotoxicity based on changes of liver red fluorescence intensity and size. In this study, we first tested four well-established hepatotoxins (acetaminophen, aspirin, isoniazid and phenylbutazone) in LiPan fry and demonstrated that these hepatotoxins could significantly reduce both liver red fluorescence and liver size in a dosage-dependent manner, thus the two measurable parameters could be used as indicators of hepatotoxicity. We then tested the LiPan fry with nine other chemicals including environmental toxicants and human drugs. Three (mefenamic acid, lindane, and arsenate) behave like hepatotoxins in reduction of liver red fluorescence, while three others (17β-estradiol, TCDD [2,3,7,8-tetrachlorodibenzo-<i>p</i>-dioxin] and NDMA [N-nitrosodimethylamine]) caused increase of liver red fluorescence and the liver size. Ethanol and two other chemicals, amoxicillin (antibiotics) and chlorphenamine (pain killer) did not resulted in significant changes of liver red fluorescence and liver size. By quantitative RT-PCR analysis, we found that the changes of red fluorescence intensity caused by different chemicals correlated to the changes of endogenous <i>fabp10a</i> RNA expression, indicating that the measured hepatotoxicity was related to fatty acid transportation and metabolism. Finally we tested a mixture of four hepatotoxins and observed a significant reduction of red fluorescence in the liver at concentrations below the lowest effective concentrations of individual hepatotoxins, suggesting that the transgenic zebrafish assay is capable of reporting compound hepatotoxicity effect from chemical mixtures. Thus, the LiPan transgenic fry provide a rapid and convenient in vivo hepatotoxicity assay that should be applicable to high-throughput hepatotoxicity test in drug screening as well as in biomonitoring environmental toxicants.</p></div

Combined hepatotoxin effect.

<p>LiPan fry were treated with a mixture of four hepatotoxins with increasing dilution factors. “1″ indicates undiluted mixture with the following final concentrations in the treatment: 2.5 mg/L acetaminophen, 1 mg/L aspirin, 1 mg/L isoniazid and 0.1 mg/L phenylbutazone. “0″ represents vehicle control groups with 0.01% DMSO. All other groups are dilutions from ½ to 1/16. Blue bars indicate liver RFP intensity and red bars refer liver size. Representative liver-specific RFP expression is shown at top of each group. Asterisks indicate statistical significance: *, P<0.05; **. P<0.01.</p

Localized expression in the yolk syncytial layer plays a role in yolk cell extension and early liver development-0

<p><b>Copyright information:</b></p><p>Taken from "Localized expression in the yolk syncytial layer plays a role in yolk cell extension and early liver development"</p><p>http://www.biomedcentral.com/1471-213X/7/117</p><p>BMC Developmental Biology 2007;7():117-117.</p><p>Published online 19 Oct 2007</p><p>PMCID:PMC2198918.</p><p></p> marker. (B, C) Ventral (B) and lateral (C) view of 12 hpf embryos with expression as detected by WISH. (D) Ventral view of 16 hpf embryos with expression of (red) and (blue) as detected by two-colour WISH. (E) Cross section of the two color hybridized embyos in (D) as indicated by the dashed line. (F, F') Magnified view of boxed region F in Panel (E). F, bright field. F', compound image of DIC/fluorescence reveals expression and position of nuclei detected by DAPI staining. Arrows indicate YSL nuclei. (G), Magnified view of boxed region G in Panel (E)