Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-10-21
pubmed:abstractText
Several studies propose that long-term enhancement of synaptic transmission between neurons results from the enlargement, perforation, and splitting of synapses and dendritic spines. Unbiased analyses through serial electron microscopy were used to assess the morphological basis for synapse spilitting in hippocampal area CA1. Few perforated synapses and almost no split (i.e., branched) spines occurred at postnatal day 15, an age of high synaptogenesis; thus, synapse splitting is unlikely to be important during development. The synapse splitting hypothesis predicts an intermediate stage of branched spines with both heads sharing the same presynaptic bouton. Ninety-one branched dendritic spines were traced through serial sections, and the different branches never synapsed with the same presynaptic bouton. Projections from spines, called "spinules," have been thought to extend from perforations in the postsynaptic density (PSD), thereby dividing the presynaptic bouton. Forty-six spinules were traced, and only 13% emerged from perforations in the PSD. Most spinules emerged from the edges of nonperforated PSDs, or from spine necks, where they extended into boutons that were not presynaptic to the spine. In summary, these morphological characteristics are inconsistent with synapse and spine splitting. An alternative is discussed whereby perforated synapses and spinules are transient components of synaptic activation, and branched spines appear from synapses forming in close proximity to one another.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9967
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
398
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
225-40
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Critical assessment of the involvement of perforations, spinules, and spine branching in hippocampal synapse formation.
pubmed:affiliation
Program in Neuroscience, Harvard Medical School, Boston, Massachusetts 02115, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't