Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2006-8-29
pubmed:abstractText
Although high levels of anxiety might be expected to negatively influence learning and memory, it remains to be shown whether individual differences in anxiety may influence spatial learning and memory in outbred rat populations. We have studied this possibility in male Wistar rats whose levels of anxiety were first characterized as either high (HA) or low (LA) according to their behavior in the elevated plus maze or in the open field test. Subsequently, their performance in the Morris water maze was studied, a task dependent on hippocampal activity. Interestingly, LA rats showed a faster acquisition and better memory in the water maze when compared to HA rats. Indeed, this difference in performance could mainly be attributed to the increase in thigmotactic behavior (swimming in circles close to the maze walls) displayed by HA rats during spatial navigation. Glucocorticoids are known to affect the state of anxiety and the hippocampus is the main target of glucocorticoids in the brain. Hence, we investigated whether the hippocampal expression of the two classical corticosteroid receptors, mineralocorticoid (MR) and glucocorticoid (GR) differed in the two groups of rats. We found that LA rats displayed higher hippocampal expression of MR but not GR than HA rats. Indeed, the expression levels for these receptors were positively correlated with the amount of time spent by the animals in the open arms of the elevated plus maze. Moreover, we present evidence that the levels of anxiety quantified in the first stages of our study constitute a trait rather than a state. Taken together, this study has generated evidence of a close interaction between the anxiety trait, hippocampal MR expression and the learning abilities of individuals in stressful spatial orientation tasks.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1074-7427
pubmed:author
pubmed:issnType
Print
pubmed:volume
86
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
150-9
pubmed:dateRevised
2007-10-17
pubmed:meshHeading
pubmed-meshheading:16580234-Analysis of Variance, pubmed-meshheading:16580234-Animals, pubmed-meshheading:16580234-Animals, Outbred Strains, pubmed-meshheading:16580234-Anxiety, pubmed-meshheading:16580234-Corticosterone, pubmed-meshheading:16580234-Exploratory Behavior, pubmed-meshheading:16580234-Hippocampus, pubmed-meshheading:16580234-Individuality, pubmed-meshheading:16580234-Male, pubmed-meshheading:16580234-Maze Learning, pubmed-meshheading:16580234-Memory, pubmed-meshheading:16580234-Rats, pubmed-meshheading:16580234-Rats, Wistar, pubmed-meshheading:16580234-Receptors, Glucocorticoid, pubmed-meshheading:16580234-Receptors, Mineralocorticoid, pubmed-meshheading:16580234-Space Perception, pubmed-meshheading:16580234-Spatial Behavior, pubmed-meshheading:16580234-Species Specificity, pubmed-meshheading:16580234-Statistics, Nonparametric, pubmed-meshheading:16580234-Temperament
pubmed:year
2006
pubmed:articleTitle
Individual differences in anxiety trait are related to spatial learning abilities and hippocampal expression of mineralocorticoid receptors.
pubmed:affiliation
Department of Psychobiology, Universidad Nacional de Educación a Distancia, Juan del Rosal 10, 28040 Madrid, Spain.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't