ABCC8 and ischemia: The study of tissues harvested 5 h after onset of ischemia (after completing the IV infusion of rtPA) showed modest immunolabeling for Sur1 in the watershed region of the anterior and middle cerebral arteries (WAM) (Fig. 1a), as well as in the watershed region of the posterior and middle cerebral arteries (WPM) (Fig. 1c).