Research OverviewSodium channels
Sodium channels (also known as "voltage-gated sodium channels") are proteins embedded in the cell membrane that conduct sodium ions through the membrane. In excitable cells such as neurons and muscle cells (myocytes), sodium channels are responsible for the rising phase of action potentials, which couple electrical nerve impulses to cellular activities such as contraction in heart muscle. Complete Information... | Research DescriptionResearch Specialties: ion channels, sodium channels, cardiac arrhythmias Voltage-dependent sodium channels have a critical role in membrane electrogenesis and repetitive firing in excitable cells. Members of this gene superfamily exhibit diffuse, tissue-specific expression in nervous, muscle, and cardiac tissues. My lab has cloned the cDNA for SCN5a, the gene for the heart voltage-dependent Na+ channel. Naturally occurring mutations in SCN5a produce cardiac arrhythmias, known as the long QT3 syndrome (LQT3), the congenital cardiac disease of abnormal rhythms that can result in sudden death. These arrhythmias are characterized by prolonged... Complete Information... |
Representative PublicationsHartmann, H.A., Mazzocca, N.J., Kleiman, R.B. and Houser, S.R. Effects of phenylephrine on calcium current and contractility of feline ventricular myocytes. Am. J. Physiol. (Heart Circ. Physiol.) 24: H1173-H1180, 1988.
Hartmann, H.A., Drewe, J.A., Kirsch, G.E., Taglialatela, M., Joho, R.H. and Brown, A.M. Exchange of conduction pathways between two related potassium channels. Science 251: 942-944, 1991.
Hartmann, H.A., Tiedeman, A.A., Chen, S-F., Brown, A.M. and Kirsch, G.E. The effects of III-IV linker mutations on human heart Na+ channel inactivation gating. Circ. Res. 75: 114-122, 1994. Complete Listing... |
