Sandi, Carmen; Davies, Heather; Isabel Cordero, M.; Rodriguez, Jose J.; Popov, Victor I. and Stewart, Michael G.
Due to copyright restrictions, this file is not available for public download
|DOI (Digital Object Identifier) Link:||http://dx.doi.org/10.1046/j.1460-9568.2003.02675.x|
|Google Scholar:||Look up in Google Scholar|
The impact was examined of exposing rats to two life experiences of a very different nature (stress and learning) on synaptic structures in hippocampal area CA3. Rats were subjected to either (i) chronic restraint stress for 21 days, and/or (ii) spatial training in a Morris water maze. At the behavioural level, restraint stress induced an impairment of acquisition of the spatial response. Moreover, restraint stress and water maze training had contrasting impacts on CA3 synaptic morphometry. Chronic stress induced a loss of simple asymmetric synapses [those with an unperforated postsynaptic density (PSD)], whilst water maze learning reversed this effect, promoting a rapid recovery of stress-induced synaptic loss within 2–3 days following stress. In addition, in unstressed animals a correlation was found between learning efficiency and the density of synapses with an unperforated PSD: the better the performance in the water maze, the lower the synaptic density. Water maze training increased the number of perforated synapses (those with a segmented PSD) in CA3, both in stressed and, more notably, in unstressed rats. The distinct effects of stress and learning on CA3 synapses reported here provide a neuroanatomical basis for the reported divergent effects of these experiences on hippocampal synaptic activity, i.e. stress as a suppressor and learning as a promoter of synaptic plasticity.
|Item Type:||Journal Article|
|Keywords:||stress; synapse reversal; water maze training|
Science > Life, Health and Chemical Sciences
|Interdisciplinary Research Centre:||Biomedical Research Network (BRN)|
|Depositing User:||Astrid Peterkin|
|Date Deposited:||16 Dec 2008 08:25|
|Last Modified:||21 Mar 2014 12:01|
|Share this page:|