Alcohol exposure leads to unrecoverable cardiovascular defects along with edema and motor function changes in developing zebrafish larvae

Maternal alcohol consumption during pregnancy can cause a series of developmental disorders in the fetus called FAS (fetal alcohol syndrome). In the present study we exposed zebrafish embryos to 1% and 2% alcohol and observed the morphology of heart and blood vessels during and after exposure to investigate motor function alterations, and damage and recovery to the cardiovascular system. The results showed that alcohol exposure could induce heart deformation, slower heart rate, and incomplete blood vessels and pericardium. After stopping exposure, larvae exposed to 1% alcohol could recover only in heart morphology, but larvae in 2% alcohol could not recover either morphology or function of cardiovascular system. The edema-like characteristics in the 2% alcohol group became more conspicuous afterwards, with destruction in the dorsal aorta, coarctation in segmental arteries and a decrease in motor function, implying more serious unrecoverable cardiovascular defects in the 2% group. The damaged blood vessels in the 2% alcohol group resulted in an alteration in permeability and a decrease of blood volume, which were the causes of edema in pathology. These findings contribute towards a better understanding of ethanol-induced cardiovascular abnormalities and co-syndrome in patients with FAS, and warns against excessive maternal alcohol consumption during pregnancy.