Fig. 7. Time dependence of vascular drift. Within the defined areas (cyan color boxes in Figs 1 and 5) the displacement of the entire vascular structure was determined using a frame-by-frame comparison of the fluorescence pattern. To eliminate adaptation artifacts occurring in the first hour of culture, displacements were measured from the second hour of recording. Data obtained from three normal (QH1 only), three anti-v (QH1 plus anti-v) and three LM609-injected (QH1 plus LM609) embryos are shown, each represented by a separate curve. Averages of control (normal and anti-v; blue) and experimentally treated (LM609; red) embryos are shown by the unbroken lines. Positive displacement represents movement in the medial direction. Exposure to LM609 resulted in a significant 88%, 73% and 70% reduction in endothelial structure displacement at 4, 6 and 8 hour time points, respectively.