UNIGE document Scientific Article
previous document  unige:10462  next document
add to browser collection
Title

LTP promotes formation of multiple spine synapses between a single axon terminal and a dendrite

Authors
Nikonenko, Irina
Bron, C. R.
Published in Nature. 1999, vol. 402, no. 6760, p. 421-425
Abstract Structural remodelling of synapses and formation of new synaptic contacts has been postulated as a possible mechanism underlying the late phase of long-term potentiation (LTP), a form of plasticity which is involved in learning and memory. Here we use electron microscopy to analyse the morphology of synapses activated by high-frequency stimulation and identified by accumulated calcium in dendritic spines. LTP induction resulted in a sequence of morphological changes consisting of a transient remodelling of the postsynaptic membrane followed by a marked increase in the proportion of axon terminals contacting two or more dendritic spines. Three-dimensional reconstruction revealed that these spines arose from the same dendrite. As pharmacological blockade of LTP prevented these morphological changes, we conclude that LTP is associated with the formation of new, mature and probably functional synapses contacting the same presynaptic terminal and thereby duplicating activated synapses.
Keywords Axons/ physiology/ultrastructureCalcium/metabolismDendrites/ physiology/ultrastructureHippocampus/physiology/ultrastructureLong-Term Potentiation/ physiologyOrgan Culture TechniquesSynapses/ physiology/ultrastructureTime Factors
Stable URL http://archive-ouverte.unige.ch/unige:10462
Full text
Identifiers
PMID: 10586883
Structures
143 hits and 0 download since 2010-08-06
Update
Export document
Format :
Citation style :