Abbreviations B6 = C57BL/6J CSS = chromosome substitution strains CSS-# = B6-Chr #A/J CSS-#F1 = (B6 × CSS-#)F1 WT = wild-type -/- = deficient Plg = plasminogen PAI-1 = plasminogen activator inhibitor-1 tPA = tissue plasminogen activator uPA = urokinase plasminogen activator SEM = standard error of the mean QTL = quantitative trait locus