 |
Previous Article | Next Article 
The Journal of Neuroscience, June 1, 1998, 18(11):4050-4062
Neuronal Nicotinic Acetylcholine Receptors Are Blocked by
Intracellular Spermine in a Voltage-Dependent Manner
Ali Pejmun
Haghighi and
Ellis
Cooper
Department of Physiology, McGill University, Montréal,
Québec, Canada H3G 1Y6
A common feature of neuronal nicotinic acetylcholine receptors
(nAChRs) is that they conduct inward current at negative membrane potentials but little outward current at positive membrane potentials, a property referred to as inward rectification. Physiologically, inward
rectification serves important functions, and the main goal of our
study was to investigate the mechanisms underlying the rectification of
these receptors. We examined recombinant 3 4 and 4 2
neuronal nAChR subtypes expressed in Xenopus oocytes and
native nAChRs expressed on superior cervical ganglion (SCG) neurons.
Whole-cell ACh-evoked currents recorded from these receptors exhibited
strong inward rectification. In contrast, we showed that single-channel
currents from these neuronal nAChRs measured in outside-out patches
outwardly rectify. On the basis of recent findings that spermine, a
ubiquitous intracellular polyamine, confers rectification to glutamate
receptors and inwardly rectifying potassium channels, we investigated
whether spermine causes neuronal nAChRs to inwardly rectify. When
spermine was added to the patch electrode in outside-out recordings, it
caused a concentration- and voltage-dependent block of ACh-evoked
single-channel currents. Using these single-channel data and
physiological concentrations of intracellular spermine, we could
account for the inward rectification of macroscopic whole-cell
ACh-evoked conductance-voltage relationships. Therefore, we conclude
that the voltage-dependent block by intracellular spermine underlies
inward rectification of neuronal nAChRs. We also found that
extracellular spermine blocks both 3 4 and
4 2 receptors; this finding points to a
mechanism whereby increases in extracellular spermine, perhaps during
pathological conditions, could selectively block these receptors.
Key words:
neuronal nAChRs; sympathetic neurons; inward
rectification; single-channel currents; spermine; voltage-dependent
block; presynaptic modulation
Copyright © 1998 Society for Neuroscience 0270-6474/98/18114050-13$05.00/0
This article has been cited by other articles:

|
 |

|
 |
 
J. Wu, Q. Liu, K. Yu, J. Hu, Y.-P. Kuo, M. Segerberg, P. A. St John, and R. J. Lukas
Roles of nicotinic acetylcholine receptor {beta} subunits in function of human {alpha}4-containing nicotinic receptors
J. Physiol.,
October 1, 2006;
576(1):
103 - 118.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
T. V. Bui, D. E. Dewey, R. E. W. Fyffe, and P. K. Rose
Comparison of the Inhibition of Renshaw Cells During Subthreshold and Suprathreshold Conditions Using Anatomically and Physiologically Realistic Models
J Neurophysiol,
September 1, 2005;
94(3):
1688 - 1698.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. H. Rolen, P. W. Sorensen, D. Mattson, and J. Caprio
Polyamines as olfactory stimuli in the goldfish Carassius auratus
J. Exp. Biol.,
May 15, 2003;
206(10):
1683 - 1696.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. Musa and R. D. Veenstra
Voltage-Dependent Blockade of Connexin40 Gap Junctions by Spermine
Biophys. J.,
January 1, 2003;
84(1):
205 - 219.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. Christophe, A. Roebuck, J. F. Staiger, D. J. Lavery, S. Charpak, and E. Audinat
Two Types of Nicotinic Receptors Mediate an Excitation of Neocortical Layer I Interneurons
J Neurophysiol,
September 1, 2002;
88(3):
1318 - 1327.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. COOPER
Nicotinic Acetylcholine Receptors on Vagal Afferent Neurons
Ann. N.Y. Acad. Sci.,
June 1, 2001;
940(1):
110 - 118.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. P. Haghighi and E. Cooper
A Molecular Link between Inward Rectification and Calcium Permeability of Neuronal Nicotinic Acetylcholine alpha 3beta 4 and alpha 4beta 2 Receptors
J. Neurosci.,
January 15, 2000;
20(2):
529 - 541.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Legendre, D. W. Ali, and P. Drapeau
Recovery from Open Channel Block by Acetylcholine during Neuromuscular Transmission in Zebrafish
J. Neurosci.,
January 1, 2000;
20(1):
140 - 148.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. Dingledine, K. Borges, D. Bowie, and S. F. Traynelis
The Glutamate Receptor Ion Channels
Pharmacol. Rev.,
March 1, 1999;
51(1):
7 - 62.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Z. Shao, I. R. Mellor, M. J. Brierley, J. Harris, and P. N. R. Usherwood
Potentiation and Inhibition of Nicotinic Acetylcholine Receptors by Spermine in the TE671 Human Muscle Cell Line
J. Pharmacol. Exp. Ther.,
September 1, 1998;
286(3):
1269 - 1276.
[Abstract]
[Full Text]
|
 |
|
|