Effect of Adamts13 gene deletion on rCBF in mice of 30-minute MCAO model. Male Adamts13^−/− (−/−) mice and wild-type (+/+) mice in an SV129-genetic background were used to study the effect of ADAMTS13 deficiency on brain ischemia: −/− (n = 25) and +/+ (n = 25) mice (8-10 weeks of age, 20-23 g of body weight). The focal cerebral ischemia (30-minute MCAO by intraluminal thread) was induced in the −/− (n = 20) and +/+ (n = 20) mice as previously described (sham surgery in −/−, n = 5; and +/+, n = 5). This study was approved by the institutional ethics committee at Nara Medical University. The rCBF was measured by LDF (ALF21; Advance Co). The rCBF was recorded over time (immediately before and after MCAO; 10, 20, and 30 minutes after MCAO; immediately after reperfusion; and 10, 20, and 30 minutes after reperfusion). The rCBFs during occlusion and reperfusion were expressed as a percentage of the baseline LDF value. The rCBF decreased to less than 20% of the baseline value during 30 minutes of MCAO and returned to the baseline immediately after reperfusion in both −/− and WT mice. The rCBF in −/− mice, however, progressively decreased more markedly compared with that in +/+ after reperfusion (percentage rCBF: −/−, n = 9, vs +/+, n = 8, at 20 and 30 minutes after reperfusion; 40.8 ± 7.1 vs 91.4 ± 9.1, and 34.6 ± 5.8 vs 83.2 ± 6.8, respectively). *P < .05 vs WT, Scheffé test after 2-way repeated-measures analysis of variance (F(8,134) = 6.668, P < .01). Values are mean ± SEM.