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Sequential changes in the synaptic structural profile following long-term potentiation in the rat dentate gyrus. II. Induction / early maintenance phase

2000; Wiley; Volume: 36; Issue: 4 Linguagem: Inglês

10.1002/(sici)1098-2396(20000615)36

1098-2396

Andrew C.W. Weeks, Tammy L. Ivanco, Janelle C. LeBoutillier, Ronald J. Racine, Ted L. Petit,

Mitochondrial Function and Pathology

SynapseVolume 36, Issue 4 p. 286-296 Sequential changes in the synaptic structural profile following long-term potentiation in the rat dentate gyrus. II. Induction / early maintenance phase Andrew C.W. Weeks, Andrew C.W. Weeks Department of Psychology and Program in Neuroscience, University of Toronto, Scarborough, Ontario M1C 1A4 CanadaSearch for more papers by this authorTammy L. Ivanco, Tammy L. Ivanco Department of Psychology, McMaster University, Hamilton, Ontario L8S 4K1 CanadaSearch for more papers by this authorJanelle C. Leboutillier, Janelle C. Leboutillier Department of Psychology and Program in Neuroscience, University of Toronto, Scarborough, Ontario M1C 1A4 CanadaSearch for more papers by this authorRonald J. Racine, Ronald J. Racine Department of Psychology, McMaster University, Hamilton, Ontario L8S 4K1 CanadaSearch for more papers by this authorTed L. Petit, Corresponding Author Ted L. Petit Department of Psychology and Program in Neuroscience, University of Toronto, Scarborough, Ontario M1C 1A4 CanadaDivision of Life Sciences, University of Toronto, 1265 Military Trail, Scarborough, ON, Canada, M1C 1A4Search for more papers by this author Andrew C.W. Weeks, Andrew C.W. Weeks Department of Psychology and Program in Neuroscience, University of Toronto, Scarborough, Ontario M1C 1A4 CanadaSearch for more papers by this authorTammy L. Ivanco, Tammy L. Ivanco Department of Psychology, McMaster University, Hamilton, Ontario L8S 4K1 CanadaSearch for more papers by this authorJanelle C. Leboutillier, Janelle C. Leboutillier Department of Psychology and Program in Neuroscience, University of Toronto, Scarborough, Ontario M1C 1A4 CanadaSearch for more papers by this authorRonald J. Racine, Ronald J. Racine Department of Psychology, McMaster University, Hamilton, Ontario L8S 4K1 CanadaSearch for more papers by this authorTed L. Petit, Corresponding Author Ted L. Petit Department of Psychology and Program in Neuroscience, University of Toronto, Scarborough, Ontario M1C 1A4 CanadaDivision of Life Sciences, University of Toronto, 1265 Military Trail, Scarborough, ON, Canada, M1C 1A4Search for more papers by this author First published: 27 April 2000 https://doi.org/10.1002/(SICI)1098-2396(20000615)36:4 3.0.CO;2-TCitations: 39AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Abstract Long-term potentiation (LTP), one of the most compelling models of learning and memory, has been associated with changes in synaptic morphology. In this study, LTP was induced and animals were sacrificed 1 h after the stimulation of the LTP group (induction / early maintenance phase). Synapses in the directly stimulated middle third of the dentate gyrus molecular layer (MML) were examined while synapses from the inner third of the dentate molecular layer (IML) of the LTP animals and both the MML and the IML of implanted animals served as controls. The total number of synapses per neuron, synaptic curvature, the presence of synaptic perforations, and the maximum length of the synaptic contact and active zone were examined. No overall change in the number of synapses per neuron was observed in the LTP tissue. LTP was associated with a significant increase in the proportion of perforated and irregular-shaped synapses compared to controls. The increase in perforated synapses was particularly apparent in the proportion of concave perforated synapses. 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