[1] Washington Univ, Sch Med, Dept Cell Biol & Physiol, St Louis, MO 63130 USA
[2] Washington Univ, Sch Med, Ctr Invest Membrane Excitabil & Dis, St Louis, MO 63130 USA
[3] Univ Med Gottingen, Dept Mol Biol, Gottingen, Germany
[4] Washington Univ, Sch Med, Div Endocrinol Metab & Lipid Res, St Louis, MO 63130 USA