QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, November 17, 2004, 24(46):10379-10383; doi:10.1523/JNEUROSCI.2104-04.2004

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (22) Citing Articles via Google Scholar Google Scholar Articles by Inchauspe, C. G. Articles by Uchitel, O. D. Search for Related Content PubMed PubMed Citation Articles by Inchauspe, C. G. Articles by Uchitel, O. D.

 Previous Article  |  Next Article 

BRIEF COMMUNICATION
Functional Compensation of P/Q by N-Type Channels Blocks Short-Term Plasticity at the Calyx of Held Presynaptic Terminal

Carlota González Inchauspe,¹ Francisco J. Martini,¹ Ian D. Forsythe,² and Osvaldo D. Uchitel¹

¹Instituto de Fisiología, Biología Molecular y Neurociencias, Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina, and ²Department of Cell Physiology and Pharmacology, University of Leicester, Leicester LE1 9HN, United Kingdom

Calcium channels of the P/Q subtype mediate transmitter release at the neuromuscular junction and at many central synapses, such as the calyx of Held. Transgenic mice in which _1A channels are ablated provide a powerful tool with which to test compensatory mechanisms at the synapse and to explore mechanisms of presynaptic regulation associated with expression of P/Q channels. Using the calyx of Held preparation from the knock-out (KO) mice, we show here that N-type channels functionally compensate for the absence of P/Q subunits at the calyx and evoke giant synaptic currents [approximately two-thirds of the magnitude of wild-type (WT) responses]. However, although evoked paired-pulse facilitation is prominent in WT, this facilitation is greatly diminished in the KO. In addition, direct recording of presynaptic calcium currents revealed that the major functional difference was the absence of calcium-dependent facilitation at the calyx in the P/Q KO animals. We conclude that one physiological function of P/Q channels is to provide additional facilitatory drive, so contributing to maintenance of transmission as vesicles are depleted during high throughput synaptic transmission.

Key words: synaptic transmission; knock-out mice; calyx of Held; calcium currents; P/Q channels; facilitation

---

Received May 31, 2004; revised September 8, 2004; accepted October 3, 2004.

This article has been cited by other articles:

				J. J. P. Alix, A. C. Dolphin, and R. Fern Vesicular apparatus, including functional calcium channels, are present in developing rodent optic nerve axons and are required for normal node of Ranvier formation J. Physiol., September 1, 2008; 586(17): 4069 - 4089. [Abstract] [Full Text] [PDF]

				E. Garcia-Perez, D. C. Lo, and J. F. Wesseling Kinetic Isolation of a Slowly Recovering Component of Short-Term Depression During Exhaustive Use at Excitatory Hippocampal Synapses J Neurophysiol, August 1, 2008; 100(2): 781 - 795. [Abstract] [Full Text] [PDF]

				T. Nakamura, T. Yamashita, N. Saitoh, and T. Takahashi Developmental changes in calcium/calmodulin-dependent inactivation of calcium currents at the rat calyx of Held J. Physiol., May 1, 2008; 586(9): 2253 - 2261. [Abstract] [Full Text] [PDF]

				R. R. Llinas, S. Choi, F. J. Urbano, and H.-S. Shin {gamma}-Band deficiency and abnormal thalamocortical activity in P/Q-type channel mutant mice PNAS, November 6, 2007; 104(45): 17819 - 17824. [Abstract] [Full Text] [PDF]

				C. G. Inchauspe, I. D. Forsythe, and O. D. Uchitel Changes in synaptic transmission properties due to the expression of N-type calcium channels at the calyx of Held synapse of mice lacking P/Q-type calcium channels J. Physiol., November 1, 2007; 584(3): 835 - 851. [Abstract] [Full Text] [PDF]

				E. Erazo-Fischer, J. Striessnig, and H. Taschenberger The Role of Physiological Afferent Nerve Activity during In Vivo Maturation of the Calyx of Held Synapse J. Neurosci., February 14, 2007; 27(7): 1725 - 1737. [Abstract] [Full Text] [PDF]

				R. L. P. Habets and J. G. G. Borst An Increase in Calcium Influx Contributes to Post-Tetanic Potentiation at the Rat Calyx of Held Synapse J Neurophysiol, December 1, 2006; 96(6): 2868 - 2876. [Abstract] [Full Text] [PDF]

				T. Ishikawa, M. Kaneko, H.-S. Shin, and T. Takahashi Presynaptic N-type and P/Q-type Ca2+ channels mediating synaptic transmission at the calyx of Held of mice J. Physiol., October 1, 2005; 568(1): 199 - 209. [Abstract] [Full Text] [PDF]

				D. Chaudhuri, B. A. Alseikhan, S. Y. Chang, T. W. Soong, and D. T. Yue Developmental Activation of Calmodulin-Dependent Facilitation of Cerebellar P-Type Ca2+ Current J. Neurosci., September 7, 2005; 25(36): 8282 - 8294. [Abstract] [Full Text] [PDF]

				M. J. Fedchyshyn and L.-Y. Wang Developmental Transformation of the Release Modality at the Calyx of Held Synapse J. Neurosci., April 20, 2005; 25(16): 4131 - 4140. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help