Heart deformity phenotypes. One-cell stage embryos were microinjected with either vehicle (control) or cortisol (32 pg/embryo) and imaged at 48 hpf for morphological deformities. Unaffected embryos (first row) were indistinguishable from wild-type embryos. Mild embryos (second row) displayed pericardial edema only (see arrow); moderate embryos (third row) displayed pericardial edema and malformed heart structures (see arrows); severe embryos (fourth row) exhibited a ruptured pericardium (see arrows) and no heartbeat was visible. Percent phenotype from multiple trials are shown as mean ± standard error of mean (SEM) (control: n = 16 trials of 37–120 embryos; cortisol: n = 14 trials of 53–184 embryos); N.D. – not detectable; indicates significant difference (Student’s t-test, p < 0.05).

Acknowledgments
This image is the copyrighted work of the attributed author or publisher, and ZFIN has permission only to display this image to its users. Additional permissions should be obtained from the applicable author or publisher of the image.

Reprinted from Molecular and Cellular Endocrinology, 363(1-2), Nesan, D., and Vijayan, M.M., Embryo exposure to elevated cortisol level leads to cardiac performance dysfunction in zebrafish, 85-91, Copyright (2012) with permission from Elsevier. Full text @ Mol. Cell. Endocrinol.