Fig. 2.

Time to fibrinolysis after infusion of tPA. The PCV of 3 dpf larvae was injured, producing a completely occluding thrombus. This was followed by either no infusion/uninjected (n = 54), infusion of saline (n = 17), 1 ng of recombinant human tPA (n = 16), or 10 ng of recombinant human tPA (n = 40), and then observation for up to 4 h. Only high concentrations of tPA at 10 ng/larvae (~5 to 10× the amount used for human therapy) were able to achieve recanalization in a fraction of larvae within 4 h and without significant toxicity. Lower concentrations of tPA did not recanalize. Bars represent median recanalization time (*P < 0.01, ****P < 0.0001 by Mantel-Cox log-rank testing).