Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have investigated by in situ hybridization changes in the content of mRNAs encoding for chromogranin B, secretogranin II, synaptin/synaptophysin and p65 after kainic acid-induced seizures and pentylenetetrazol kindling. Kainic acid seizures resulted in marked but transient increases in secretogranin II mRNA concentrations in the granule cell layer and throughout the pyramidal cell layers of the hippocampus (by 100-500%) as well as in various areas of the cerebral cortex (by up to 900%) and the thalamus (up to 300%) 12 h after injection of the toxin. Chromogranin B mRNA concentrations were persistently increased in granule cells (but not in pyramidal cells) of the hippocampus (suprapyramidal blade, 450%) and in cortical areas (250%) at all time intervals after kainic acid injection (12 h to 60 days). Accordingly chromogranin B immunoreactivity was enhanced in the terminal field of mossy fibers and in the inner part of the molecular layer 30 days after kainic acid. Secretogranin II immunoreactivity was also markedly increased in CA1, the paraventricular thalamic nucleus and in the central amygdala. In rats kindled with pentylenetetrazol only chromogranin B (by 200%) but not secretogranin II mRNA was increased in dentate granule cells. In contrast to the mRNAs of these secretory proteins concentrations of mRNAs encoding synaptin/synaptophysin and p65, two membrane proteins of synaptic vesicles, were not altered in any of these brain structures. These data demonstrate that in brain the biosynthesis of chromogranin B and secretogranin II is regulated like that of neuropeptides which is consistent with a role of these secretory polypeptides as precursors of functional peptides. Activation of neurons induces an increased synthesis of neuropeptides but not a concomitant synthesis of membrane proteins of synaptic vesicle. This might lead to an increased quantal content available for transmission.
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PMID:Temporal lobe epilepsy of the rat: differential expression of mRNAs of chromogranin B, secretogranin II, synaptin/synaptophysin and p65 in subfield of the hippocampus. 133 87

Aberrant neural sprouting of mossy fiber terminals in the supragranular layer of dentate gyrus is consistently observed following seizures in an animal model of epilepsy. It is also observed in hippocampi taken from epileptic patients with hippocampal sclerosis. The aberrant neural sprouting with synaptic reorganization is one of the proposed cellular mechanisms underlying epileptogenesis. It is not known whether aberrant synaptogenesis can be induced in the cortex, as in hippocampus, by seizure activity. In this study, synaptic terminals in the cortex were measured after focal cortical seizures by a semiquantitative image analysis of synaptophysin immunoreactivity. Brief intracortical perfusion of kainic acid induced focal status epilepticus and destructive cortical lesions. Synaptophysin immunoreactivity was significantly increased in the area where kainic acid was perfused. The increase of synaptophysin immunoreactivity, indicating an increase of synaptogenesis, was observed at 2 and 4 weeks after focal cortical seizures. This result suggests that kainic acid-induced seizure activity is associated with long-lasting synaptogenesis in the cortex. Studies centering on the physiological consequences of aberrant synaptogenesis may lead to additional understanding of the mechanisms underlying cortical epileptogenesis.
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PMID:Kainic acid-induced focal cortical seizure is associated with an increase of synaptophysin immunoreactivity in the cortex. 879 64

The molecular mechanisms that underlie dentate granule cell axon (i.e., mossy fiber) growth during development and following seizure-induced hippocampal injury remain unknown. Part of this process may involve specific factors that support dentate granule cells during differentiation, and molecular cues that allow the appropriate growth of mossy fiber axons toward their targets. To study this process, we developed an in vitro assay system to measure the activity of putative trophic, chemoattractant and chemorepulsive factors. Two-hundred-micrometer-thick transverse hippocampal sections were prepared from neonatal rats and microdissected to isolate the middle one-third of the superior blade of the dentate granule cell layer. These were embedded in a three-dimensional collagen matrix either alone or with microdissected regions of the CA2 pyramidal cell layer. Cultures were maintained in a defined medium and grown for two to three days in a standard culture environment. Results showed that numerous processes grew primarily from the hilar side of explants into the collagen matrix, often in excess of 500 microns in length. These were determined to be axons based on: (i) morphological criteria including size and presence of growth cones, (ii) synaptophysin and growth-associated protein-43 immunoreactivity, (iii) lack of glial fibrillary acidic protein immunoreactivity and (iv) contiguity of biocytin-filled processes with neuronal soma within the explant. Treatment of cultures with brain-derived neurotrophic factor caused a significant increase in axon number and length, and this effect was partially reversed by the addition of a trkB-immunoglobulin fusion protein that blocks the activity of brain-derived neurotrophic factor and neurotrophin-4/5. Basic fibroblast growth factor also caused a marked increase in axon number and length, and caused a migration of neuron-like cells out of the explant into the collagen. These results show that cultured dentate granule cell layer explants are capable of growing mossy fibers into a neutral collagen matrix, and the growth of axons can be modified by the addition of exogenous growth factors. Furthermore, since target tissue and point sources of purified factors can easily be co-cultured with the explants, this new system provides a direct means for testing the molecular cues that influence mossy fiber growth.
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PMID:Dentate granule cell layer collagen explant cultures: spontaneous axonal growth and induction by brain-derived neurotrophic factor or basic fibroblast growth factor. 889 86

Gangliogliomas are common in childhood, but rare in infancy. The authors report a rare case of ganglioglioma who had an initial episode of complex partial seizure in infancy. A two-year-old girl was admitted for the surgical treatment of intractable seizures. She presented with an annual episode of seizure at two months old. The CT scan at 2 months old showed a light high-density tumor in the left medial temporal lobe. However, she had no treatment because she had no seizure since then and her psychomotor development was normal. She was treated with anticonvulsants from 1 year and 10 months old since seizures recurred. She was admitted to our ward at 2 years old because the frequency of seizures increased. Plain CT on admission showed an enlarged high density mass in left medial temporal lobe. The T1 weighted images of MRI demonstrated the mass to be isointense compared with the cortex, with homogeneously contrast enhancement. Total removal of the tumor was performed and histological diagnosis was ganglioglioma. She is seizure-free after surgery and synaptophysin was useful for the histological diagnosis. This case may indicate that gangliogliomas can be a congenital brain tumor which slowly enlarges.
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PMID:[A case of infantile ganglioglioma]. 892 19

We describe a characteristic pattern of immunoreactivity for synaptophysin in tuberous sclerosis. We analyzed cortical tubers from surgical specimens taken from six patients with tuberous sclerosis, which were obtained by surgical resections for the treatment of intractable seizures. The cortical tubers were characterized by blurred lamination of the cerebral cortex, hypercellularity, and gliotic changes. Neuropil in the cortex of cortical tubers showed reduced immunoreactivity for synaptophysin in all patients. 'Giant cells' were investigated in the cortex and white matter regions of cortical tubers. Some 'giant cells' had neuronal characteristics such as Nissl substance, a centrally placed chromatin-marginated nucleus, prominent nucleolus, positive immunoreactivity for microtubule-associated protein 2, and negative immunoreactivity for glial fibrillary acidic protein. Other 'giant cells' were indeterminate in cell type because they lacked Nissl bodies, distinct nucleolus, consistent immunoreactivity for microtubule-associated protein 2 and glial fibrillary acidic protein. Almost all 'neuronal giant cells' and some of the 'indeterminate giant cells' in the white matter showed intense immunoreactivity for synaptophysin: cell borders were surrounded by an intense immunoreactive halo. In conclusion, these immunohistochemical patterns for synaptophysin assist in characterizing these abnormal cells in the cortical tubers of patients with tuberous sclerosis.
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PMID:Giant cells in cortical tubers in tuberous sclerosis showing synaptophysin-immunoreactive halos. 907 86

Using apolipoprotein E knockout mice derived from the Maeda source [Piedrahita J. A. et al. (1992) Proc. natn. Acad Sci. US.A. 89, 4471 4475], we have studied the influence of apolipoprotein E gene deletion on normal CNS function by neurological tests and water maze learning, hippocampal ultrastructure assessed by quantitative immunocytochemistry and electron microscopy, CNS plasticity, i.e. hippocampal long-term potentiation and amygdaloid kindling, and CNS repair, i.e. synaptic recovery in the hippocampus following deafferentation. In each study there was little difference between the apolipoprotein E knockout mice and wild-type controls of similar age and genetic background. Apolipoprotein E knockout mice aged eight months demonstrated accurate spatial learning and normal neurological function. Synaptophysin and microtubule-associated protein 2 immunohistochemistry and electron microscopic analysis of these animals revealed that the hippocampal synaptic and dendritic densities were similar between genotypes. The induction and maintenance of kindled seizures and hippocampal long-term potentiation were indistinguishable between groups. Finally, unilateral entorhinal cortex lesions produced a marked loss of hippocampal synaptophysin immunoreactivity in both groups and a marked up-regulation of apolipoprotein E in the wild-type group. Both apolipoprotein E knockout and wild-type groups showed immunohistochemical evidence of reactive synaptogenesis, although the apolipoprotein E knockout group may have initially shown greater synaptic loss. It is suggested that either apolipoprotein E is of no importance in the maintenance of synaptic integrity and in processes of CNS plasticity and repair, or more likely, alternative (apolipo)proteins may compensate for the loss of apolipoprotein E in the knockout animals.
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PMID:Behavioural, physiological and morphological analysis of a line of apolipoprotein E knockout mouse. 1033 88

Dysembryoplastic neuroepithelial tumor (DNT) is a relatively new neuroepithelial neoplasm that was first described by Daumas-Duport et al. in 1988. It was incorporated in the revised World Health Organization classification of brain tumors in 1993. The authors present the first case of DNT reported in the Latin-American literature. A 16-year-old woman had been found at age of five years to have complex partial seizures accompanied by secondary generalization. She was treated with various anti-epileptic drugs but always with incomplete control of seizures activity. Neurological examination was normal. Magnetic resonance imaging demonstrated a lesion in the left temporal lobe. She underwent a craniotomy with complete resection of the tumor. Histological study showed atypical neuroglial proliferation characteristic of DNT. Monoclonal antibody immunostaining for glial fibrillary acidic protein and S-100 protein confirmed the glial component, and neuronal specific enolase and synaptophysin emphasized the neuronal component.
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PMID:[Dysembryoplastic neuroepithelial tumor. Case report]. 962 69

We report a case of a 15-year-old girl with new onset seizures, who had a mixed dysembryoplastic neuroepithelial tumor (DNT) and ganglioglioma of the right parieto-occipital lobe. The tumor appeared well demarcated and exhibited a low T1 and a high T2 signal on magnetic resonance imaging. Architecturally it was in large part intracortical and multinodular, but also featured a leptomeningeal component. The former corresponded to DNT, a proliferation of oligodendroglia-like cells (OLCs) arranged in nodules, as well as comprising a diffuse internodular element featuring "floating neurons" in a mucoid matrix. The leptomeningeal portion of the lesion was a ganglioglioma consisting of large neurons and astrocytes in association with marked desmoplasia. Spatially, the two components abutted one another but appeared distinct. Immunohistochemistry showed the neurons of the ganglioglioma to be positive for class III beta-tubulin, synaptophysin, and chromogranin A, whereas the astrocytic cells stained only for glial fibrillary acidic protein. Most OLCs in the DNT were positive for S-100 protein. This apparently mixed lesion suggests that a close histogenetic relationship exists between DNT and ganglioglioma. We postulate that the pluripotential progenitor cells residing in the subpial granular layer may have given rise to the cortical DNT and to the leptomeningeal ganglioglioma. To our knowledge, this is the first detailed histological, immunochemical and ultrastructural report of a mixed DNT and ganglioglioma.
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PMID:Mixed dysembryoplastic neuroepithelial tumor and ganglioglioma. 965 Jul 58

Dysembryoplastic neuroepithelial tumor (DNT) is a recently described rare brain neoplasm with characteristic clinical and morphological features and favorable prognosis. We report here two cases of DNT. The first concerned a 12 years old girl who presented complex seizures preceded by acoustic aura (melodies). Computed tomography revealed a hypodense tumor measuring 2 x 2.5 cm in diameter, located paracortically in the left temporal lobe. The second tumor was removed from a 21-year-old man with partial complex seizures. Nine years earlier patient underwent neurosurgery with partial removal of the tumor The tumor's histopathologic diagnosis is unfortunately lacking. Computed and magnetic resonance imaging showed a mass occupying the cortex and paracortical areas of the anterior pole of the temporal lobe. Histologically, both tumors consisted of small, S-100 protein immunopositive oligodendrocyte-like cells (OLCs) arranged between synaptophysin- and, to a lesser degree, NFP-immunopositive axons (glioneuronal element). In the second case, an area of pilocytic astrocytoma-like appearance was also found, these cells were immunopositive for GFAP. The present study provides clinical, radiological and histological data, which may be helpful in differential diagnosis of this newly recognised brain tumor.
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PMID:Clinical, radiological and histological presentations of dysembryoplastic neuroepithelial tumors (DNT). Report of two cases. 981 23

Interpretation of data from gene targeting studies can be confounded by the inherent traits of the background inbred strains used in the generation of transgenic and null mutant mice. We have therefore compared the behaviour and response to CNS injury of four inbred strains commonly used in molecular genetic studies to produce models of neurological disease. Adult, male 129/Ola, BALB/c, C57BL/6 and FVB/N mice (2-4 months) were initially subjected to behavioural tests that comprised a neurological examination, determination of motor function and cognitive testing in the Morris water maze. Also the response to CNS injury following an acute kainic acid (KA) challenge (30 mg kg-1, i.p.) was determined. The 129/Ola and BALB/c strains showed significant motor deficits when compared with the C57BL/6 and FVB/N strains. In contrast, only the FVB/N strain showed evidence of apparent cognitive impairments in the water maze as evidenced by increased pathlengths to locate the escape platforms and impaired performance in a probe trial. In addition, the FVB/N strain showed the most severe seizure response and mortality rate (62%) following administration of KA (30 mg kg-1, i.p.). These behavioural changes were also associated with a greater degree of cell body and synaptophysin loss in the pyramidal CA3 hippocampal cell layer and astrogliosis 72-h post-dose. These data suggest that the FVB/N strain may not be the most suitable background strain for the development of new transgenic mice for the study of genes implicated in the learning and memory process.
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PMID:Behavioural analysis and susceptibility to CNS injury of four inbred strains of mice. 987 17


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