Abstract 11809: Trans-Endothelial Electrical Resistance to Assess Cell Layer Integrity in Coronary Artery Endothelial Cells After Hypoxia/Reoxygenation Injury

Introduction: Cardiovascular disease remains one of the leading causes of complications and death worldwide. Therefore, accurate and reliable methods of mimicking ischemia/reperfusion (IR) injury in cardiac cells in vivo are crucial when testing drugs/substances for prevention and treatment. Coronary artery endothelial cells play a critical role in not only supplying blood to myocardial cells but protecting them from insult as well. However, the endothelial layer can be compromised by ischemic injury, heightening damage to the heart during reperfusion. Hypothesis: Varied ischemic insult of mouse coronary artery endothelial cells (MCAECs) affects cell layer integrity as measured by Trans-Endothelial Electrical Resistance (TEER). Methods: MCAECs were cultured on Grenier Bio-One ThinCert™-cell culture inserts for 72 hrs to allow for adequate confluency. Cells were then subjected to either continued normoxic conditions or hypoxia for 3, 6, 12, or 24 hrs, with a 2-hr reperfusion period immediately following. TEER was used to measure the integrity of the endothelial cell layer on the insert. Results: Our data showed a significant decrease in TEER between control and hypoxic groups after 6 hrs (p = 0.0400), 12 hrs (p = 0.0179) and 24 hrs (p = 0.0103), but not after 3 hrs (p = 0.4453) of hypoxia. Conclusion: This indicates that titrating the hypoxia time to a sufficient duration is necessary to achieve an adequate H/R injury which can then be used for potential cardioprotective agents and/or strategies to be tested. Furthermore, TEER is a reliable and reproducible method to assess the role of endothelial cell membrane integrity in cardioprotection.