Biophysical Journal 11: 211-234 (1971)
© 1971 the Biophysical Society

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Poussart, D. J. M. Search for Related Content PubMed PubMed Citation Articles by Poussart, D. J. M.

Membrane Current Noise in Lobster Axon under Voltage Clamp

ABSTRACT

Random fluctuations in the steady-state current of neural membrane were measured in the giant lobster axon by means of a low noise voltage-clamp system. The power density spectrum S(f) of the fluctuations was evaluated between 20 and 5120 Hz and found to be of the type 1/f. Mean values of the potassium, sodium, and leakage currents _K, _Na, and _L were also measured by usual voltage-clamp techniques. Comparisons between these two types of data recorded under a number of different experimental conditions, such as presence of tetrodotoxin (TTX), substitution of calcium by lanthanum, and changes in the external concentration of potassium, have strongly suggested that the intensity of the fluctuations is related to the magnitude of _K.