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  • H Hodges
  • 1996
Open mazes are primarily designed to measure place learning and memory, using environmental visuospatial cues. However, maze tasks differ along many dimensions, including (1) types of apparatus, which vary from arenas (water maze: WM) to highly structured routes (radial-arm maze: RAM); (2) availability of visuospatial, associative or sensory cues; (3) task(More)
Spatial deficits were assessed in male Wistar rats which had undergone 4 vessel occlusion for 5, 10, 15 or 30 min. Relationships between the extent of brain damage, the duration of 4-vessel occlusion, and the behavioural impairment consequent upon ischaemia were investigated. Starting 13-18 days after occlusion, rats were trained to find a hidden platform(More)
When animals are exposed to a stimulus that has no consequences they are subsequently impaired in learning that this stimulus predicts an important event, such as footshock. This retarding effect of stimulus pre-exposure is called latent inhibition (LI) and is reliably disrupted by amphetamine, antipsychotics having an opposite effect. The present(More)
The CA1 and hilar fields of the hippocampus are highly vulnerable to lack of oxygen after interruption of blood flow to the brain. Severe anterograde memory loss, seen in a significant proportion of heart attack survivors, has been attributed to selective bilateral ischaemic damage to the hippocampus. Animal models of global ischaemia, induced by(More)
Hippocampal cell loss was induced by the four-vessel occlusion (4VO) method, a model of global ischaemia. Global ischaemia for 15 min induced a selective damage to the CA1 subfield. Occlusion for 25 min produced a larger cell loss within the CA1 and more variably the CA2, CA3, the striatum and cortex. Ischaemic and sham control groups were assessed on two(More)
Groups of rats which had undergone global ischaemia for 10, 15 or 20 min using the four-vessel occlusion technique were compared with sham-operated controls on learning to locate a submerged platform in both acquisition and working memory tasks in a standard Morris water maze, and in a working memory task in an eight-channel water radial maze. Ischaemic(More)
The purpose of this study was to evaluate the temporal and spatial pathological alterations within ischemic tissue using serial magnetic resonance imaging (MRI) and to determine the extent and duration of functional impairment using objective behavioral tests after transient middle cerebral artery occlusion (tMCAO) in the rat. MRI signatures derived from(More)
In order to assess effects of global ischemia in tasks of spatial learning and working memory, male Wistar rats were subjected to four vessel occlusion (4 VO) for periods of 5, 10, and 20 min and compared with sham-operated controls over four test phases, from 6 to 54 weeks after surgery. Rats were assessed on acquisition in the water maze, a task that is(More)
4-Amino-2-(4-methyl-1-piperazinyl)-5-(2,3,5-trichlorophenyl)pyrimidine (BW619C89) is a sodium channel antagonist which when administered parenterally reduces neurological deficit and infarct volume after middle cerebral artery occlusion in rats. We have investigated whether BW619C89 administered orally before middle cerebral artery occlusion is(More)
BACKGROUND AND PURPOSE Grafts of MHP36 cells have previously been shown to reduce dysfunction after global ischemia in rats. To test their efficacy after focal ischemia, MHP36 cells were grafted 2 to 3 weeks after transient intraluminal middle cerebral artery occlusion (tMCAO) in rats. METHODS MHP36 cells were implanted into the hemisphere contralateral(More)