Abstract P280: Deletion of Cardiac Ankyrin Repeat Kinase Reduces Ischemia/Reperfusion Injury in the Heart in Vivo

Ischemic heart disease impacts millions of Americans and can progress to heart failure. Current therapies do not address this progression and new therapeutic targets are needed. One novel potential target is cardiac ankyrin repeat kinase (CARK, also troponin I interacting kinase; TNNI3K). CARK is expressed only in the heart and is significantly up-regulated in failing human hearts. Beyond this, little is known about CARK’s biological roles. To determine CARK’s function in the injured heart we subjected transgenic (Tg) mice expressing wild-type or kinase-inactive (KI) CARK to 30 minutes of LV ischemia followed by 24 hours of reperfusion (I/R). CARK-Tg mice had significantly larger infarcts (32.2% AAR vs 16.1% in WT littermates, p<0.05) following I/R. Cardiac troponin I (cTnI) serum levels were also significantly elevated in CARK-Tg mice after 24h, consistent with increased injury. Conversely, infarct size was decreased in mice expressing KI CARK and levels of cTnI were reduced, suggesting that blocking CAR...