Effect of solenopsin on vascular development in zebrafish. Confocal images of drug-treated embryos shown here are primarily lateral or dorsolateral views of the trunk vasculature of different TG(fli1:EGFP)^y1 embryos at 32 hours after fertilization. In both panels (A, 10 ×; B, 25 ×), i and iii represent solenopsin 3–treated embryos while ii and iv represent solenopsin A–treated embryos at 5 and 6 μg/mL, respectively. (A) In i and iii, the primary sprouts from the dorsal aorta and posterior cardinal vein have split at the level of the dorsolateral surface of the neural tube, and branches from adjacent primary sprouts are interconnected to form the paired longitudinal anastomotic vessels (DLAV; white arrowhead). In ii and iv, the primary sprouts (red arrowhead) have delayed considerably in reaching the dorsolateral surface of the neural tube. (B) In high power (25 ×), the absence of DLAV is denoted by an arrow (iv), and the spacing between the sprouts (white arrowhead in iv; red arrowhead in ii) is distinct.