Neurophysiology

, Volume 16, Issue 1, pp 14–21 | Cite as

Activation and inactivation of batrachotoxin-modified sodium channels in the frog nerve fiber membrane

  • G. N. Mozhaeva
  • A. P. Naumov
  • B. I. Khodorov
Article
Received:

Abstract

Currents through batrachotoxin (BTX)-modified sodium channels were measured under voltage clamp conditions on the Ranvier node membrane. Potential-dependence of the fraction of activated BTX-modified channels was determined on the basis of data showing nonlinearity of the momentary current-voltage characteristic curve in the region of high negative potentials. BTX induces a shift of the sodium channel activation curve toward negative potentials on average by 67 mV, but does not, under these circumstances, alter the potential-sensitivity of their activation mechanism. The results of experiments with preliminary depolarization, of varied amplitude and duration, showed that BTX-modified sodium channels are capable of partial inactivation. The high level of steady-state conduction of the modified channels is evidently due to the fact that as a result of modification by BTX the open state of the channel becomes energetically more advantageous than the inactivated state. It is concluded that the action of BTX on inactivation differs in principle from the action of pronase.

Keywords

Sodium Channel Negative Potential Activation Curve Voltage Clamp Fiber Membrane 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Plenum Publishing Corporation 1984

Authors and Affiliations

  • G. N. Mozhaeva
  • A. P. Naumov
  • B. I. Khodorov

There are no affiliations available

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