Use of the single electrode voltage clamp to perform noise and relaxation studies of acetylcholine-activated channels in Aplysia neurons.
Journal Article
The single electrode voltage clamp has been used to perform fluctuation analysis ("noise" analysis) and relaxation experiments in order to study the average lifetime and conductance of ACh-activated sodium channels in Aplysia neurons. Measured values of average channel lifetime, which is approximately 20 msec at --80 mV and 11 degrees C, and elementary conductance, which is approximately 8 pS, are consistent with previously published results using two electrode clamping. The frequency response of the clamp was evaluated to determine its capabilities and limitations for the study of membrane currents. Sinusoidal currents injected into a voltage-clamped model membrane to simulate the frequency components of membrane noise are accurately reproduced at frequencies up to 500 Hz. Following a voltage clamp command, the new membrane potential is established in less than 2 msec, and current relaxations recorded after that time can be used to determine average channel lifetime. Since the frequency response of the clamp is much greater than the average lifetime of ACh-activated channels in Aplysia neurons, the single electrode voltage clamp is comparable to conventional two-electrode systems for investigating the properties of these channels, and may also be useful in other systems in which the time course of membrane currents is much slower than the frequency response of the clamp.
Full Text
Duke Authors
Cited Authors
- Wachtel, RE; Wilson, WA
Published Date
- June 1981
Published In
Volume / Issue
- 4 / 1
Start / End Page
- 87 - 103
PubMed ID
- 6265713
Pubmed Central ID
- 6265713
Electronic International Standard Serial Number (EISSN)
- 1872-678X
International Standard Serial Number (ISSN)
- 0165-0270
Digital Object Identifier (DOI)
- 10.1016/0165-0270(81)90021-2
Language
- eng