1 Department of Cell Biology and Physiology, University of North Carolina-Chapel Hill School of Medicine, Chapel Hill, North Carolina; Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
2 Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, North Carolina State University, Chapel Hill, North Carolina. Electronic address: legantw@email.unc.edu.