An interdisciplinary approach will be used to elucidate the structure and function of the voltage-dependent sodium channel from E. electrophorus electroplax. Biochemical methods will be employed to study the binding of tetrodotoxin and saxitoxin to a component of the sodium channel, and factors affecting the equilibrium and kinetic binding parameters of toxin-binding in intact membranes and detergent extracts will be determined and compared. This will hopefully increase our understanding of the molecular nature of the toxin binding site, and help determine its relationship to the channel component responsible for ion selectivity. Immunological methods will be used to ascertain whether the purified tetrodotoxin/saxitoxin binding site is associated with molecular structures responsible for other channel functionalities, such as voltage-sensitive gating. Antibodies will be raised to purified toxin sites, with the goal of generating physiologically-active antibodies affecting other sodium channel sites. Such antibodies could be used chemical probes and labels with which to correlate various sodium channel functions with their corresponding structures, and as a means to determine sodium channel in certain autoimmune neuromuscular diseases. Electrophysiological methods, mainly voltage-clamp studies, will be used to determine the functional affects of immunological and biochemical compounds.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS015879-06
Application #
3396508
Study Section
Physiology Study Section (PHY)
Project Start
1979-12-01
Project End
1987-11-30
Budget Start
1984-12-01
Budget End
1985-11-30
Support Year
6
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of Colorado Denver
Department
Type
Schools of Medicine
DUNS #
065391526
City
Aurora
State
CO
Country
United States
Zip Code
80045
Wang, Ze-Jun; Snell, Lawrence D; Tabakoff, Boris et al. (2002) Inhibition of neuronal Na+ channels by the novel antiepileptic compound DCUKA: identification of the diphenylureido moiety as an inactivation modifier. Exp Neurol 178:129-38
Martinez, A M (1999) Distribution of sodium and potassium channels as well as myelin associated glycoprotein (MAG) during the early stages of Wallerian degeneration. J Submicrosc Cytol Pathol 31:73-81
Novakovic, S D; Levinson, S R; Schachner, M et al. (1998) Disruption and reorganization of sodium channels in experimental allergic neuritis. Muscle Nerve 21:1019-32
Vabnick, I; Messing, A; Chiu, S Y et al. (1997) Sodium channel distribution in axons of hypomyelinated and MAG null mutant mice. J Neurosci Res 50:321-36
Bennett, E; Urcan, M S; Tinkle, S S et al. (1997) Contribution of sialic acid to the voltage dependence of sodium channel gating. A possible electrostatic mechanism. J Gen Physiol 109:327-43
Deerinck, T J; Levinson, S R; Bennett, G V et al. (1997) Clustering of voltage-sensitive sodium channels on axons is independent of direct Schwann cell contact in the dystrophic mouse. J Neurosci 17:5080-8
England, J D; Happel, L T; Kline, D G et al. (1996) Sodium channel accumulation in humans with painful neuromas. Neurology 47:272-6
England, J D; Levinson, S R; Shrager, P (1996) Immunocytochemical investigations of sodium channels along nodal and internodal portions of demyelinated axons. Microsc Res Tech 34:445-51
Vabnick, I; Novakovic, S D; Levinson, S R et al. (1996) The clustering of axonal sodium channels during development of the peripheral nervous system. J Neurosci 16:4914-22
Wu, B Q; Yang, L; Kao, C Y et al. (1996) 11-Oxo-tetrodotoxin and a specifically labelled 3H-tetrodotoxin. Toxicon 34:407-16

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