Previous studies in mouse have shown that blood flow plays a crucial role in aortic arch remodeling. To investigate if this was the case in zebrafish, we performed laser-assisted microsurgery to sever the connection between aa5 and aa6 to the ventral aorta on one side of the embryo (top left). This blocked flow to aa5 and aa6 on the right side of the embryo, while sparing the aortic arches themselves. We found that this led to a block in angiogenic sprouting from the aortic arches lacking blood flow, although sprouting on the control side of the embryo proceeded normally (bottom left panel). We noted similar defects on both sides of the embryo when we completely stopped blood flow using chemical or genetic means (right panels). These observations indicated that blood flow was essential for angiogenesis of the aortic arch blood vessels in zebrafish.
Blood flow is required for aortic arch angiogenesis
