The gamma-aminobutyric acid (GABA) antagonist, bicuculline, induces generalized motor seizures when injected into a discrete site ('area tempestas') in the deep prepiriform cortex at concentrations considerably lower than those that induce convulsions from closely adjacent areas or other forebrain sites such as amygdala and hippocampus. This observation prompted the suggestion that the area tempestas is a crucial epileptogenic site involved in seizure generation. In the present study, the region functionally defined as area tempestas in rats was bilaterally destroyed by microinjection of ibotenic acid. Systemic administration of bicuculline induced generalized motor seizures in both lesioned and non-lesioned animals without any indication of differences in seizure severity or latency. This argues against the suggestion that the deep prepiriform cortex plays a crucial role in the generation of seizures following systemic administration of GABA antagonists.
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http://dx.doi.org/10.1016/0304-3940(90)90724-n | DOI Listing |
Cells Tissues Organs
March 2003
Max Planck Institute of Biophysical Chemistry, Göttingen, Germany.
The mammalian primary olfactory system consists of a set of different telencephalic structures, including paleo-, archi-, periarchi- and mesocortical components. We present the first characterisation of the normal and connectional anatomy of the primary olfactory cortex of the common marmoset, a microsmatic simian species increasingly used in primate research. The centrifugal and centripetal bulbar projections were determined by injections of the anterograde and retrograde tracer wheat germ agglutinin-conjugated horseradish peroxidase and fluorescent dyes into the ipsilateral main olfactory bulb.
View Article and Find Full Text PDFPoult Sci
September 2001
C. and O. Vogt Institute of Brain Research, Heinrich Heine University, Düsseldorf, Germany.
A comparison of brain size and brain composition was made between two uncrested duck breeds and Crested Ducks (CR) and between CR individuals that do possess crests and those that do not have the crest. Domestic ducks of the breed CR have allometrically larger brains than uncrested duck breeds. The crest inserts on a cushion of fat and connective tissue that is partly nourished by brain vessels via small holes in the skull.
View Article and Find Full Text PDFJ Neurochem
July 1997
Department of Neurology, University of Pittsburgh, Pennsylvania 15213, Tokyo,
An area of the deep prepiriform cortex is a controlling site for limbic seizures. Focal pharmacologic blockade of NMDA receptors in the deep prepiriform cortex protects against hippocampal cell injury during limbic seizures induced by intravenous kainate and during the excitotoxicity of global ischemia. In the current study, the deep prepiriform cortex was lesioned bilaterally by microinjection of kainate, 3 days before 10 min of global ischemia induced by four-vessel occlusion.
View Article and Find Full Text PDFBrain Res
April 1997
Department of Neurology, University of Pittsburgh, PA 15213, USA.
The present study investigates the role of pharmacologic blockade of NMDA (N-methyl-D-aspartate) and non-NMDA receptors at deep prepiriform cortex (area tempestas, AT) in neuronal injury during prolonged seizures in rat. Status epilepticus was induced by intravenous kainate (15 mg/kg) and neuronal death was assessed in hippocampal CA3 sector 72 h following status epilepticus. Unilateral equimolar microinjections of 2-amino-7-phosphonoheptanoic acid (AP-7), an NMDA receptor antagonist, or 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX), a non-NMDA receptor antagonist, into AT were given prior to kainate administration.
View Article and Find Full Text PDFJ Cereb Blood Flow Metab
March 1997
Department of Neurology, University of Pittsburgh, Pennsylvania 15213, USA.
Deep prepiriform cortex has an important role in modulating neurotransmission during limbic seizures. We used pharmacologic blockade of non-N-methyl-D-aspartate (NMDA) receptors to study excitatory circuitry from the deep prepiriform cortex to the hippocampus during global ischemia in rat. NBQX, a potent non-NMDA glutamate receptor antagonist, was microinjected stereotactically into the deep prepiriform cortex before global ischemia for 10 min.
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