Post-learning hippocampal sharp wave-ripples (SWRs) generated during slow wave sleep are thought to play a crucial role in memory formation. While in Alzheimer's disease, abnormal hippocampal oscillations have been reported, the functional contribution of SWRs to the typically observed spatial memory impairments remains unclear. These impairments have been related to degenerative synaptic chang...

This study examined intermittent, high-frequency (100-200 Hz) oscillatory patterns in the CA1 region of the hippocampus in the absence of theta activity, i.e., during and in between sharp wave (SPW) bursts. Pyramidal and interneuronal activity was phase-locked not only to large amplitude (>7 SD from baseline) oscillatory events, which are present mainly during SPWs, but to smaller amplitude (<4...

Human hippocampal choline decreases in major depression episodes. This decrease was recently measured by our group and it has been found that its level normalizes during electroconvulsive therapy. We hypothesized a hippocampal choline increase in the rat brain under electroconvulsive shock (ECS) treatment in an animal model of depression (Learned Helplessness). Method: Rat hippocampi were inves...

objective(s):growing evidence indicates that extract of ginkgo biloba (egb) attenuates hippocampal-dependent memory deficit in aged individuals; however, very little is known about the effect of egb on the structure of hippocampus. therefore we examined the egb-induced morphological changes of the cornu ammonis (ca) region in aged rats. materials and methods: sixteen aged male wistar rats, 24 m...

oxidative stress plays a major role in the pathogenesis of alzheimer's disease (ad) of sporadic origin. the expression of dhcr24 (seladin-1), marker for neuronal oxidative stress and degeneration, has been reported to be altered in the brains of ad patients. in the present study, we investigated the effect of trimetazidine (tmz) on the hippocampal oxidative parameters and the expression of dhcr...

introduction: it has been reported that oral morphine dependency facilitated formation of spatial learning and memory. in the present study the role of nmda receptors located in hippocampal ca1 area of morphine dependent rats was studied. methods: male rats were divided into 4 groups. two cannulae were stereotaxically implanted bilaterally into the hippocampal ca1 area. after 5 days recovery, a...

introduction mdma or ecstasy is a derivative of amphetamines used mostly by young people worldwide. although the acute effects of this drug are known, the effect of chronic administration is not well studied. therefor the aim of this study was to determine the effects of repeated (long term) administration of mdma on rats&apos; memory and their hippocampal cell density. method: young adult male...

introduction: stress is defined as any environmental change that disturbs the maintenance of brain homeostasis. stress leads to production of pro-inflammatory cytokines that provoke neurodegenerative disorders. in the present study, we investigated the effects of dalteparin on hippocampal neuronal death induced by chronic stress in rats. methods: the study was carried out on 60 adult male wista...

OBJECTIVES Hippocampal avoidance during whole-brain radiotherapy is performed to prevent neural stem cell injury causing neurocognitive dysfunction. Nevertheless, the estimated risk of metastases in hippocampal avoidance area in small-cell lung cancer is unknown. The current study aimed to characterize the metastatic distribution within the brain relative to the hippocampus, estimate the incide...

Fiber volleys (FVs) from the stratum lucidum of rat hippocampal area CA3 were recorded extracellularly from in vitro slices in the presence of 10 mM kynurenic acid. In agreement with previous work, bulk stimulation of the dentate gyrus (DG) near the hilar border leads to an asynchronous FV. Transection of the stratum lucidum between the DG stimulation site and the CA3 recording site reduced or ...