Ionic current through batrachotoxin-modified sodium channels of the ranvier node membrane at high positive and negative potentials

1984 ◽  
Vol 15 (5) ◽  
pp. 357-363
Author(s):  
G. N. Mozhaeva ◽  
A. P. Naumov ◽  
B. I. Khodorov
Keyword(s):  
Sodium Channels ◽  
Ionic Current ◽  
Ranvier Node

Effect of aconitine on some properties of the sodium channels of the ranvier node membrane

1976 ◽  
Vol 8 (2) ◽  
pp. 127-134
Author(s):  
G. N. Mozhaeva ◽  
A. P. Naumov ◽  
Yu. A. Negulyaev
Keyword(s):  
Sodium Channels ◽  
Ranvier Node

Differences in the blocking action of benzocaine and amines on batrachotoxin-modified sodium channels of the Ranvier node

1983 ◽  
Vol 14 (6) ◽  
pp. 468-474 ◽  
Author(s):  
L. D. Zaborovskaya ◽  
B. I. Khodorov
Keyword(s):  
Sodium Channels ◽  
Ranvier Node

Displacement currents in sodium channels of the ranvier node membrane

1977 ◽  
Vol 8 (4) ◽  
pp. 314-319
Author(s):  
A. V. Lonskii ◽  
V. I. Il'in ◽  
I. E. Katina ◽  
Z. I. Krutetskaya
Keyword(s):  
Sodium Channels ◽  
Ranvier Node ◽  
Displacement Currents

Stimulus-dependent blockade of sodium channels of the Ranvier node membrane by the phenothiazine derivative ethmozine

1982 ◽  
Vol 13 (4) ◽  
pp. 285-292
Author(s):  
V. M. Bolotina ◽  
S. V. Revenko ◽  
B. I. Khodorov
Keyword(s):  
Sodium Channels ◽  
Ranvier Node ◽  
Phenothiazine Derivative

Kinetics of interaction of scorpion toxin with sodium channels in the Ranvier node membrane

1981 ◽  
Vol 12 (6) ◽  
pp. 409-415 ◽  
Author(s):  
G. N. Mozhaeva ◽  
A. P. Naumov
Keyword(s):  
Sodium Channels ◽  
Scorpion Toxin ◽  
Ranvier Node ◽  
Kinetics Of

scholarly journals Computer simulation of the effect of the nodal gap resistance on ionic current measurements in the Ranvier node membrane

1981 ◽  
Vol 36 (3) ◽  
pp. 797-802 ◽  
Author(s):  
C. Zaciu ◽  
M. Tripşa ◽  
V. Vasilescu
Keyword(s):  
Computer Simulation ◽  
Ionic Current ◽  
Ranvier Node

scholarly journals Modification of inactivation in cardiac sodium channels: ionic current studies with Anthopleurin-A toxin.

1995 ◽  
Vol 106 (4) ◽  
pp. 601-616 ◽  
Author(s):  
D A Hanck ◽  
M F Sheets
Keyword(s):  
Steady State ◽  
Sodium Channels ◽  
Time Course ◽  
Sodium Current ◽  
Ionic Current ◽  
Na Channel ◽  
Channel Activation ◽  
Time To Peak ◽  
Cardiac Purkinje Cells ◽  
Cardiac Sodium Channels

The site 3 toxin, Anthopleurin-A (Ap-A), was used to modify inactivation of sodium channels in voltage-clamped single canine cardiac Purkinje cells at approximately 12 degrees C. Although Ap-A toxin markedly prolonged decay of sodium current (INa) in response to step depolarizations, there was only a minor hyperpolarizing shift by 2.5 +/- 1.7 mV (n = 13) of the half-point of the peak conductance-voltage relationship with a slight steepening of the relationship from -8.2 +/- 0.8 mV to -7.2 +/- 0.8 mV (n = 13). Increases in Gmax were dependent on the choice of cation used as a Na substitute intracellularly and ranged between 26 +/- 15% (Cs, n = 5) to 77 +/- 19% (TMA, n = 8). Associated with Ap-A toxin modification time to peak INa occurred later, but analysis of the time course INa at multiple potentials showed that the largest effects were on inactivation with only a small effect on activation. Consistent with little change in Na channel activation by Ap-A toxin, INa tail current relaxations at very negative potentials, where the dominant process of current relaxation is deactivation, were similar in control and after toxin modification. The time course of the development of inactivation after Ap-A toxin modification was dramatically prolonged at positive potentials where Na channels open. However, it was not prolonged after Ap-A toxin at negative potentials, where channels predominately inactivate directly from closed states. Steady state voltage-dependent availability (h infinity or steady state inactivation), which predominately reflects the voltage dependence of closed-closed transitions equilibrating with closed-inactivated transitions was shifted in the depolarizing direction by only 1.9 +/- 0.8 mV (n = 8) after toxin modification. The slope factor changed from 7.2 +/- 0.8 to 9.9 +/- 0.9 mV (n = 8), consistent with a prolongation of inactivation from the open state of Ap-A toxin modified channels at more depolarized potentials. We conclude that Ap-A selectively modifies Na channel inactivation from the open state with little effect on channel activation or on inactivation from closed state(s).

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