Shin-ichi Sakurai

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Quantitative autoradiography of [3H]MK-801 binding was used to characterize regional differences in N-methyl-D-aspartate (NMDA) receptor pharmacology in rat CNS. Regionally distinct populations of NMDA receptors were distinguished on the basis of regulation of [3H]MK-801 binding by the NMDA antagonist 3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid(More)
[3H]MK-801 binding in rat brain was characterized using a quantitative autoradiographic binding assay. [3H]MK-801 binding (5 nM) reached equilibrium by 120 min at 23 degrees C. [3H]MK-801 appeared to label a single high affinity site with an affinity constant of approximately 11 nM. [3H]MK-801 binding was heterogeneously distributed throughout the brain(More)
The striatum receives the majority of excitatory amino acidergic input to the basal ganglia from neocortical and allocortical sources. The subthalamic nucleus and the substantia nigra also receive excitatory amino acidergic inputs from neocortex. The subthalamic nucleus, which has prominent projections to the pallidum and nigra, is the only known intrinsic(More)
Receptor autoradiography was used to study the laminar distribution of excitatory amino acid, GABA(A), and GABA(B) binding sites in human striate cortex. Binding sites for all these receptor subtypes were found within striate cortex, but there were marked differences in the laminar distribution of binding sites. NMDA binding sites were most dense in layers(More)
PET-demonstrated decreases in [11C]flumazenil binding occur in anterior mesial temporal structures on the side of epileptogenesis in unilateral mesial temporal lobe epilepsy. We performed quantitative autoradiography on anterior mesial and lateral temporal specimens from 11 subjects with unilateral mesial temporal lobe epilepsy and six neurologically normal(More)
The effect of Zn2+ on t-[3H]butylbicycloorthobenzoate ([3H]TBOB) binding to the GABAA receptor complex was studied autoradiographically in rat brain. Zn2+ inhibited [3H]TBOB binding in a dose-dependent manner at physiological concentrations. Saturation analysis revealed noncompetitive inhibition in various brain regions. The inhibitory effect of Zn2+ had(More)
With the aim of detecting the timing of p53 and Ki-ras gene alterations in the gastric adenoma-carcinoma sequence, 19 early gastric adenocarcinomas arising from adenomas were studied. Immunohistochemically, 5 adenocarcinomas were positive for p53; 3 focally and 2 diffusely. The p53 point mutations were detected in a focal area with p53 immunoreactivity in 2(More)
We studied excitatory and inhibitory amino acid binding sites autoradiographically in control and multiple system atrophy (MSA) cerebella. Within the dentate nucleus (DN) of MSA specimens, we found a significant increase in the level of GABAA, benzodiazepine, and metabotropic binding sites compared with controls. In the granule cell layer, kainate,(More)
The picrotoxinin ligand [3H]t-butylbicycloorthobenzoate ([3H] TBOB) was evaluated as an autoradiographic ligand to study gamma-aminobutyric acidA (GABAA) receptors. Specific [3H]TBOB binding was approximately 80% of total binding, was saturable and identified a single population of binding sites with regional Kd approximating 30 nM. [3H]TBOB binding was(More)
We used receptor autoradiography to determine the distribution of excitatory and inhibitory amino acid neurotransmitter binding sites in the cerebellar cortex of the pigeon (Columba livia). alpha-Amino-3-hydroxy-5-methylisoxazole-4-propionic acid, kainate and metabotropic binding sites had highest levels in the molecular layer. N-methyl-D-aspartate binding(More)