Very Negative Potential for Half-inactivation of, and Effects of Anions on, Voltage-dependent Sodium Currents in Acutely Isolated Rat Olfactory Receptor Neurons

2000 ◽  
Vol 175 (2) ◽  
pp. 123-138 ◽  
Author(s):  
W. Qu ◽  
A.J. Moorhouse ◽  
S. Rajendra ◽  
P.H. Barry
Keyword(s):  
Olfactory Receptor ◽  
Negative Potential ◽  
Olfactory Receptor Neurons ◽  
Sodium Currents ◽  
Voltage Dependent ◽  
Receptor Neurons ◽  
Isolated Rat

scholarly journals Properties of transient K+ currents and underlying single K+ channels in rat olfactory receptor neurons.

1991 ◽  
Vol 97 (5) ◽  
pp. 1043-1072 ◽  
Author(s):  
J W Lynch ◽  
P H Barry
Keyword(s):  
Steady State ◽  
Olfactory Receptor ◽  
Olfactory Receptor Neurons ◽  
Simple Method ◽  
Small Component ◽  
Inactivation Curve ◽  
K Channels ◽  
Voltage Dependent ◽  
Steady State Inactivation ◽  
Receptor Neurons

The transient potassium current, IK(t), of enzymatically dissociated rat olfactory receptor neurons was studied using patch-clamp techniques. Upon depolarization from negative holding potentials, IK(t) activated rapidly and then inactivated with a time course described by the sum of two exponential components with time constants of 22.4 and 143 ms. Single-channel analysis revealed a further small component with a time constant of several seconds. Steady-state inactivation was complete at -20 mV and completely removed at -80 mV (midpoint -45 mV). Activation was significant at -40 mV and appeared to reach a maximum conductance at +40 mV (midpoint -13 mV). Deactivation was described by the sum of two voltage-dependent exponential components. Recovery from inactivation was extraordinarily slow (50 s at -100 mV) and the underlying processes appeared complex. IK(t) was reduced by 4-aminopyridine and tetraethylammonium applied externally. Increasing the external K+ concentration ([K+]o) from 5 to 25 mM partially removed IK(t) inactivation, usually without affecting activation kinetics. The elevated [K+]o also hyperpolarized the steady-state inactivation curve by 9 mV and significantly depolarized the voltage dependence of activation. Single transient K+ channels, with conductances of 17 and 26 pS, were observed in excised patches and often appeared to be localized into large clusters. These channels were similar to IK(t) in their kinetic, pharmacological, and voltage-dependent properties and their inactivation was also subject to modulation by [K+]o. The properties of IK(t) imply a role in action potential repolarization and suggest it may also be important in modulating spike parameters during neuronal burst firing. A simple method is also presented to correct for errors in the measurement of whole-cell resistance (Ro) that can result when patch-clamping very small cells. The analysis revealed a mean corrected Ro of 26 G omega for these cells.

scholarly journals Whole Mount Immunolabeling of Olfactory Receptor Neurons in the Drosophila Antenna

10.3791/51245 ◽  
2014 ◽  
Author(s):  
M. Rezaul Karim ◽  
Keita Endo ◽  
Adrian W Moore ◽  
Hiroaki Taniguchi
Keyword(s):  
Olfactory Receptor ◽  
Olfactory Receptor Neurons ◽  
Whole Mount ◽  
Receptor Neurons
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