| |
Fig. 7. Overexpression of VEGF alters vascular patterning. All em- bryos were photographed at 40X magnification. Anterior is to the right in all panels. A: Lateral view of stage 35 embryo showing the normal pattern of X-msr expression. Stained regions include the posterior cardinal veins and an undefined tissue at the tip of the tail. B,C: Lateral views of posterior portion of VEGF injected embryos, at about stage 33, showing groups of extraneous endothelial cells extending ventrally from the posterior cardi- nal veins. D: Lateral view of the posterior portion of a VEGF injected embryo, at about stage 35, showing large ectopic blood vessels in the posterior gut that are continuous with the posterior cardinal veins. Additional vessels sprouting anteriorly from this ectopic vascular structure are also visible. E: Ventral view of a control stage 46 embryo stained with benzidine. A single major vessel, the subintestinal vein, is present in this embryonic region (white arrowhead). The heart is indicated by a white arrow. F: Ventral view of a VEGF injected stage 46 embryo stained with benzidine. Injection of VEGF results in substantial alterations to the normal vascular organization, with an increase in the amount and complexity of vascular tissues (black arrowhead). The heart is indicated by a white arrow. G: Lateral view of the tail of a normal stage 46 embryo stained with benzidine. H: Lateral view of the tail of a VEGF injected embryo. Disorganized ectopic vessels are visible in the anterior portion of the tail, above the caudal artery. |
