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

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, December 6, 2006, 26(49):12647-12655; doi:10.1523/JNEUROSCI.3678-06.2006

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 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 Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Zhao, J.-P. Articles by Constantine-Paton, M. Search for Related Content PubMed PubMed Citation Articles by Zhao, J.-P. Articles by Constantine-Paton, M.

 Previous Article  |  Next Article 

Development/Plasticity/Repair
Long-Term Potentiation in the Juvenile Superior Colliculus Requires Simultaneous Activation of NMDA Receptors and L-type Ca²⁺ Channels and Reflects Addition of Newly Functional Synapses

Jian-Ping Zhao, Marnie A. Phillips, and Martha Constantine-Paton

The McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

Correspondence should be addressed to Jian-Ping Zhao, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 46-4165, Cambridge, MA 02139. Email: jpzhao{at}mit.edu

The visual layers of the rodent superficial superior colliculus (sSC) have been the focus of many development studies of the molecular bases of retinotopic map formation, the role of early retinal waves in this process, and the development of glutamate synapses. Previous studies have documented long-term potentiation (LTP), believed to be critical to developmental synapse refinement, in the rodent sSC. However, the means of induction and the preparations used have varied widely, and thus cellular changes underlying this LTP remain ambiguous. Whole-cell and perforated patch clamping were used in this study to elucidate the cellular mechanism of electrically evoked LTP in the juvenile rat sSC. This LTP required relatively low-frequency stimulation (20 Hz) and simultaneous activation of NMDA receptors and L-type Ca²⁺ channels. Experiments focused on narrow-field vertical neurons, a documented excitatory cell type in the stratum griseum superficiale using bipolar stimulation in the stratum opticum. Strontium (Sr²⁺) replacement of calcium (Ca²⁺) was applied to study evoked quantal events before and after LTP induction at the same synapses. Paired-pulse ratio and coefficient of variance analyses examined presynaptic release. Increases in quantal frequency were invariably found in the absence of increases in quantal amplitude and probability of release. These data suggest that electrically stimulated LTP, in the juvenile sSC after eye opening, selectively involves the addition or stabilization of AMPA receptors at the large number of silent synapses known to appear in the sSC after eye opening.

Key words: LTP; NMDA receptors; L-type Ca²⁺ channels; silent synapses; quantal frequency; probability of release

---

Received Aug. 23, 2006; revised Oct. 23, 2006; accepted Oct. 30, 2006.

Correspondence should be addressed to Jian-Ping Zhao, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Building 46-4165, Cambridge, MA 02139. Email: jpzhao{at}mit.edu

This article has been cited by other articles:

				R. D. Shah and M. C. Crair Retinocollicular Synapse Maturation and Plasticity Are Regulated by Correlated Retinal Waves J. Neurosci., January 2, 2008; 28(1): 292 - 303. [Abstract] [Full Text] [PDF]

				J.-P. Zhao and M. Constantine-Paton NR2A / Mice Lack Long-Term Potentiation But Retain NMDA Receptor and L-Type Ca2+ Channel-Dependent Long-Term Depression in the Juvenile Superior Colliculus J. Neurosci., December 12, 2007; 27(50): 13649 - 13654. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help