EDN1 and ischemia: In MCAs and ACAs, significantly enhanced contractile responses to ET-1 were observed at 3 days post-ischemia compared to MCAs and ACAs from sham-operated rats, whereas in 0 h, 5 days and 7 days of ischemia-reperfusion groups, the ET-1 induced contractions in MCAs and ACAs were not changed compared to sham (Fig. 1A).