Work

Identification and Characterization of a Ca2+-Sensitive Nonspecific Cation Channel Underlying Prolonged Repetitive Firing inAplysiaNeurons

Year: 1996

Type: article

Abstract: The afterdischarge of Aplysia bag cell neurons has served as a model system for the study of phosphorylation-mediated changes in neuronal excitability. The nature of the depolarization generating the afterdischarge, however, has remained unclear. We now have found that venom from Conus textile triggers a similar prolonged discharge, and we have identified a slow inward current and corresponding channel, the activation of which seems to contribute to the onset of the discharge. The slow inward current is voltage-dependent and Ca(2+)-sensitive, reverses at potentials slightly positive to O mV, exhibits a selectivity of K approximately equal to Na >> Tris > N-methyl-D-glucamine (NMDG), and is blocked by high concentrations of tetrodotoxin. Comparison of these features with those observed in channel recordings provides evidence that a Ca(2+)-sensitive, nonspecific cation channel is responsible for a slow inward current that regulates spontaneous repetitive firing and suggests that modulation of the cation channel underlies prolonged changes in neuronal response properties.

Source: Journal of Neuroscience

DOI: 10.1523/jneurosci.16-11-03661.1996

Authors: Gisela F. Wilson, Frank C. Richardson, Thomas E. Fisher, Baldomero M. Olivera, Leonard K. Kaczmarek

Institutions: Yale University, University of Utah

Language: English

Topic: Ion channel regulation and function

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: hybrid

Funders: National Institutes of Health, National Institute of Neurological Disorders and Stroke

Awards: G1071942159, SECOND MESSENGER REGULATION OF GROWTH CONE PROPERTIES, G6068104129, Biochemical Control of Excitability in Neurons