 |
||||
|
||||
|
||||
|
||||
Previous Article | Next Article
The Journal of Neuroscience, November 1, 1998, 18(21):8758-8769
Depolarization Selectively Increases the Expression of the Kv3.1 Potassium Channel in Developing Inferior Colliculus Neurons
Si-qiong J. Liu and Leonard K. Kaczmarek Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520-8066
The Kv3.1 channel subunit, when expressed heterologously, gives rise to a high-threshold noninactivating potassium current. Experiments with auditory neurons have suggested that the presence of this channel subunit enables them to fire action potentials at high frequencies. We have found that the expression levels of Kv3.1 transcripts increase in inferior colliculus neurons before the onset of hearing and then remain relatively constant. Because spontaneous neuronal activity plays an important role in modulating neuronal excitability during development, we examined the effects of depolarization with an elevated concentration of external potassium ions on the expression of Kv3.1 channel subunits in immature inferior colliculus neurons. Elevated potassium produced a marked increase in Kv3.1 mRNA levels and in the amplitude of a high-threshold, noninactivating current before the onset of hearing. This increase was prevented by the presence of a calcium channel blocker, indicating that calcium influx mediated the depolarization-induced increase in this current. In contrast, treatment with an elevated external potassium concentration caused only a moderate increase in the peak amplitude of a lower-threshold inactivating current. The repolarization of action potentials in the high-potassium-treated cells was more rapid and complete than in the control cells. Computer simulations confirmed that this change could be explained by a change in Kv3.1-like current of the same magnitude as recorded in voltage-clamp experiments. Thus, depolarization and calcium influx may alter the excitability of immature inferior colliculus neurons by selectively increasing the levels of a Kv3.1-like potassium current.
Key words: potassium channel; expression; depolarization; inferior colliculus; Kv3.1; calcium
Copyright © 1998 Society for Neuroscience 0270-6474/98/18218758-12$05.00/0
This article has been cited by other articles:
I. L. Hanganu, A. Okabe, V. Lessmann, and H. J. Luhmann
Cellular Mechanisms of Subplate-Driven and Cholinergic Input-Dependent Network Activity in the Neonatal Rat Somatosensory Cortex
Cereb Cortex, April 24, 2008; (2008) bhn061v1.
[Abstract] [Full Text] [PDF]
F. V. Chirila, K. C. Rowland, J. M. Thompson, and G. A. Spirou
Development of gerbil medial superior olive: integration of temporally delayed excitation and inhibition at physiological temperature
J. Physiol., October 1, 2007; 584(1): 167 - 190.
[Abstract] [Full Text] [PDF]
B. Yang, R. Desai, and L. K. Kaczmarek
Slack and Slick KNa Channels Regulate the Accuracy of Timing of Auditory Neurons
J. Neurosci., March 7, 2007; 27(10): 2617 - 2627.
[Abstract] [Full Text] [PDF]
W. Marcotti, A. Erven, S. L. Johnson, K. P. Steel, and C. J. Kros
Tmc1 is necessary for normal functional maturation and survival of inner and outer hair cells in the mouse cochlea
J. Physiol., August 1, 2006; 574(3): 677 - 698.
[Abstract] [Full Text] [PDF]
W. J. Moody and M. M. Bosma
Ion Channel Development, Spontaneous Activity, and Activity-Dependent Development in Nerve and Muscle Cells
Physiol Rev, July 1, 2005; 85(3): 883 - 941.
[Abstract] [Full Text] [PDF]
R. H. Casavant, C. M. Colbert, and S. E. Dryer
A-Current Expression is Regulated by Activity but not by Target Tissues in Developing Lumbar Motoneurons of the Chick Embryo
J Neurophysiol, November 1, 2004; 92(5): 2644 - 2651.
[Abstract] [Full Text] [PDF]
R. Corlew, M. M Bosma, and W. J Moody
Spontaneous, synchronous electrical activity in neonatal mouse cortical neurones
J. Physiol., October 15, 2004; 560(2): 377 - 390.
[Abstract] [Full Text] [PDF]
R. N. Leao, A. Berntson, I. D. Forsythe, and B. Walmsley
Reduced low-voltage activated K+ conductances and enhanced central excitability in a congenitally deaf (dn/dn) mouse
J. Physiol., August 15, 2004; 559(1): 25 - 33.
[Abstract] [Full Text] [PDF]
C. A. A. von Hehn, A. Bhattacharjee, and L. K. Kaczmarek
Loss of Kv3.1 Tonotopicity and Alterations in cAMP Response Element-Binding Protein Signaling in Central Auditory Neurons of Hearing Impaired Mice
J. Neurosci., February 25, 2004; 24(8): 1936 - 1940.
[Abstract] [Full Text] [PDF]
A. Yamaguchi, L. K. Kaczmarek, and D. B. Kelley
Functional Specialization of Male and Female Vocal Motoneurons
J. Neurosci., December 17, 2003; 23(37): 11568 - 11576.
[Abstract] [Full Text] [PDF]
A. Vincent, N. J. Lautermilch, and N. C. Spitzer
Antisense Suppression of Potassium Channel Expression Demonstrates Its Role in Maturation of the Action Potential
J. Neurosci., August 15, 2000; 20(16): 6087 - 6094.
[Abstract] [Full Text] [PDF]
S. Buckingham and A. Spencer
K(+) currents in cultured neurones from a polyclad flatworm
J. Exp. Biol., January 10, 2000; 203(20): 3189 - 3198.
[Abstract]
|
|
|
|
 |
|