Figure 2.
Isoproterenol decreased ST segment elevation in SUR2 mice. A. Baseline ECG recordings of control and SUR2 null mice. SUR2 null mice exhibit spontaneous episodes of coronary vasospasm evidenced by ST segment elevation on ECG. Episodes vary in length and usually resolve within 3 minutes; an example of vasospasm is shown under SUR2 KO. B. ECG recordings immediately following isoproterenol injection. Control mice (n=3/3) exhibited ST segment depression, while no ST segment depression or other ECG abnormality was observed in SUR2 null mice during the resulting tachycardic period (n=0/5). C. Quantification of ST segment elevation before and after drug administration in SUR2 null mice. While coronary vasospasm was present in all SUR2 null mice at baseline, none was observed during tachycardia.