Search results for "Subiculum"
showing 9 items of 9 documents
Conditioned orienting (alpha) and delayed behavioral and evoked neural responses during classical conditioning
1989
A differentiation of short-latency (alpha) and long-latency (delayed) classically conditioned behavioral and evoked neural (hippocampal) responses was attempted. Further, facilitation and retardation of these responses were studied in an experimental design in which 10 paired conditioning sessions either preceded (CC-CO group) or followed (CO-CC group) 10 randomly unpaired presentations of conditioned stimuli (CS) and unconditioned stimuli (UCS). A 2024-ms tone (1000 Hz) was delivered directly through a miniature earphone to the left ear, eliciting an orienting head movement ('alpha' response) to the left. The unconditioned stimulus (UCS) was a direct 1024-ms stimulation of the lateral hypo…
Non-granule PSA-NCAM immunoreactive neurons in the rat hippocampus
2002
The polysialylated form of the neural cell adhesion molecule (PSA-NCAM) continues to be expressed in the adult hippocampus, mainly in a subset of neurons located in the innermost portion of the granule cell layer. PSA-NCAM immunoreactive neurons have also been described outside this layer in humans, where they are severely reduced in schizophrenic brains. Given this important clinical implication, we were interested in finding whether similar neurons existed in the adult rat hippocampus and to characterize their distribution, morphology and phenotype. PSA-NCAM immunocytochemistry reveals labeled neurons in the subiculum, fimbria, alveus, hilus, and stratum oriens, lucidum and radiatum of CA…
Differential associations of age with volume and microstructure of hippocampal subfields in healthy older adults
2015
Hippocampal atrophy in advanced healthy aging has frequently been reported. However, the vulnerability of different hippocampal subfields to age-related atrophy is still a source of debate. Moreover, the association of age with the microstructural integrity of subfields is largely unknown. In this study, we investigated the associations between age and volume as well as microstructural integrity of hippocampal subfields using a three-dimensional (3D) surface mapping approach. Forty-three healthy older adults spanning the age range from 60 to 85 years underwent T1-weighted and diffusion-tensor imaging. Analyses demonstrated an association of age with hippocampal volume predominantly in the m…
The evolutionary history and tissue mapping of GPR123: specific CNS expression pattern predominantly in thalamic nuclei and regions containing large …
2007
The Adhesion family of G protein-coupled receptors (GPCRs) includes 33 receptors and is the second largest GPCR family. Most of these proteins are still orphans and fairly little is known of their tissue distribution and evolutionary context. We report the evolutionary history of the Adhesion family protein GPR123 as well as mapping of GPR123 mRNA expression in mouse and rat using in situ hybridization and real-time PCR, respectively. GPR123 was found to be well conserved within the vertebrate lineage, especially within the transmembrane regions and in the distal part of the cytoplasmic tail, containing a potential PDZ binding domain. The real-time PCR data indicates that GPR123 is predomin…
IC‐P‐024: Localization of hippocampal atrophy in Alzheimer's disease
2011
The hippocampus presents the highest rate of atrophy in the early stage of Alzheimer's disease (AD), with more pronounced neuron loss reported in CA1 and subiculum. The aim of this study is to increase the discrimination power of hippocampal shape analysis between AD and normal controls (NC) by focusing on the subregions with atrophy associated with AD and describing the localized shape changes using statistical shape models (SSMs).
Auditory cortical and hippocampal-system mismatch responses to duration deviants in urethane-anesthetized rats.
2013
Any change in the invariant aspects of the auditory environment is of potential importance. The human brain preattentively or automatically detects such changes. The mismatch negativity (MMN) of event-related potentials (ERPs) reflects this initial stage of auditory change detection. The origin of MMN is held to be cortical. The hippocampus is associated with a later generated P3a of ERPs reflecting involuntarily attention switches towards auditory changes that are high in magnitude. The evidence for this cortico-hippocampal dichotomy is scarce, however. To shed further light on this issue, auditory cortical and hippocampal-system (CA1, dentate gyrus, subiculum) local-field potentials were …
Acamprosate blocks the increase in dopamine extracellular levels in nucleus accumbens evoked by chemical stimulation of the ventral hippocampus.
2003
Recently, we have shown that acamprosate is able to modulate extracellular dopamine (DA) levels in the nucleus accumbens (NAc) and may act as an antagonist of N-methyl-D-aspartate (NMDA) receptors. Neurochemical studies show that chemical stimulation (using NMDA) of the ventral subiculum (vSub) of the hippocampus produces robust and sustained increases in extracellular DA levels in the NAc, an effect mediated through ionotropic glutamate (iGlu) receptors. The present study examines whether acamprosate locally infused in the NAc of rats could block or attenuate the increase in NAc extracellular DA elicited by chemical stimulation (with 5 mM NMDA) of the ventral subiculum of the hippocampus. …
Temporospatial expression of HSP72 and c-JUN, and DNA fragmentation in goat hippocampus after global cerebral ischemia
2001
The role of gene induction (expression of HSP72 and c-JUN proteins) and delayed ischemic cell death (in situ labeling of DNA fragmentation) have been investigated in the goat hippocampus after transient global cerebral ischemia. The animals were subjected to 20-min ischemia (bilateral occlusion of the external carotid arteries plus bilateral jugular vein compression) and allowed to reperfuse for 2 h, and then 1, 3, and 7 days. Histological signs of cell loss were not found in the hippocampus at 2 h, 1 day, or 3 days of reperfusion. However, such an ischemic insult produced extensive, selective, and delayed degeneration in the hippocampus, as 68% of the neurons in CA1 had died at 7 days, but…
Stage-dependent and sector-specific neuronal loss in hippocampus during Alzheimer's disease
2000
Recent stereological studies documented a severe loss of hippocampal neurons in end-stage Alzheimer's disease. The development of the disease, however, is progressive and slow, over clinically inconspicuous decades. The Braak-staging system distinguishes six histopathological stages some of which are not accompanied by clinical symptoms. We analyzed hippocampal cell loss in correlation to Braak stages. Neuron numbers were determined with unbiased stereological principles in a defined subportion of the hippocampus of 28 subjects. There were no age-dependent neuronal losses in any of the hippocampal subdivisions examined. Compared to stage I, pyramidal cell loss in CA1 was reduced by 33% in s…