ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

THE expression of three phosphoinositide-specific phospholipase C (PLC) isotypes in rat olfactory epithelium was investigated using monoclonal antibodies. In intact animals, PLCβ1 was not expressed in the olfactory epithelium but was found in glands below the epithelium. However, following unilateral olfactory bulbectomy (OBX), PLCβ1 was expressed in the dendrites of some olfactory receptor neurons, primarily in the endoturbinates on the unoperated side. PLCγ1 immunoreactivity was found in the apices of sustentacular cells and in glands below the epithelium. PLCδ1 immunoreactivity was found in the glands and in the perinuclear region and dendrites of some receptor neurons. Since none of the PLC isotypes studied were expressed in the cilia of receptor neurons, the results suggest that another PLC isotype is likely to be involved in mediating olfactory transduction.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

WITH the purpose of mapping representations of the finger and proximal arm in the human primary motor cortex (MI), we measured regional cerebral blood flow (rCBF) in eight right-handed normal volunteers during self-paced finger and proximal arm movements. Each movement activated two-different fields in MI, one located deep in the anterior lip of the central sulcus and the other relatively close to the surface of the precentral gyrus. Arm fields were located higher than finger fields. A superficial arm field and a deep finger field partially, overlapped. The results indicate that there are two spatially separate motor representations of the finger and proximal arm in the human MI.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

THE striatum is composed of two compartments arranged as a mosaic, the striosomes (patches) and the matrix, which differ in their neurochemical and neuroanatomical properties. Along with a large number of neurotransmitter-related differences, these regions have recently been shown to differ in their immediate early gene (IEG) response to indirect dopamine agonists. Both Fos and Krox 24 can be preferentially induced in the striosomal compartment of the striatum by amphetamine. This compart-mentalization of response suggests that there are functionally distinct molecular signalling pathways in striosomes and matrix. This paper examines the response of Krox 24 to i.p. administration of the cannabinoid agonist CP55,940 and demonstrates a selective induction of this protein within the striosomes 2 h after drug administration. This result suggests that cannabinoid receptors may regulate striatal gene expression.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

THE transcriptional expression of the mitogen-inducible cyclo-oxygenase (COX-2) was investigated byin situhybridization of kainate-treated rat brains. Kainate treatment rapidly induced COX-2 mRNA in neurons throughout the forebrain which was blocked by pretreatment with MK-801 or NBQX. Transient expression of COX-2 mRNA lasting about 8 h occurred in areas that were resistant to neuronal necrosis, while COX-2 mRNA expression persisted for 24–72 h in regions that were vulnerable. These results show that seizures result in increased COX-2 expression and support the hypothesis that COX-2 could be an important factor in the pathogenesis of delayed neuronal necrosis due to kainate excitotoxicity.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

PHOSPHORYLATION of the astrocytic marker protein glial fibrillary acidic protein (GFAP) in hippocampal slices from immature rats is stimulated by glutamate agonists via a metabotropic receptor. In this study we investigated the modulation of this stimulation by guanine nucleotides. Recent work has shown that guanine nucleotides inhibit the binding of kainate to its receptors in a manner independent of G proteins. Gpp(NH)p, GDP-β-S and GMP inhibited by approximately 50% the stimulation of GFAP phosphorylation by glutamate or 1S,3R-ACPD. In the case of glutamate and Gpp(NH)p it was shown that the inhibition was dose dependent. These results indicate that guanine nucleotides can inhibit glutamate-stimulated phosphorylation responses by interaction with a cell surface metabotropic receptor.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

PART of the gene encoding cionin from the protochordateCiona intestinaliswas amplified by polymerase chain reaction from genomic DNA employing synthetic oligonucleotides designed from the reported cDNA sequence. The nucleotide sequence of this gene revealed the presence of two introns of 350 and 57 bp which interrupt the region that encodes pre-pro-cionin. A comparison of the positions of the exon/intron boundaries of the cionin and mammalian gastrin/cholecystokinin genes revealed a different exon/intron pattern. The 5‘-donor and 3’-acceptor splice sites found in the cionin gene, however, are in agreement with the mammalian consensus sequence.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

SPECIFIC antibodies raised against a fusion protein containing the amino acid sequence of the putative second intracellular loop of the cloned 5-HT,-A receptor subunit were used for the immunohistochemical visualization of 5-HT, receptors in the rat spinal cord. A dense 5-HT,-like immunoreactivity was found in the superficial layers of the dorsal horn, which closely matched the labelling of 5-HT, binding sites by [125I]iodo-zacopride. This immuno-staining was markedly decreased following unilateral rhizotomy, consistently with a preferential location of 5-HT, receptors on terminals of primary afferent fibres, and with the presence of 5-HT, mRNA in dorsal root ganglia. However, a significant proportion of 5-HT, receptors persisted after rhizotomy, and the corresponding mRNA was found in the dorsal horn of the spinal cord. 5-HT, receptors are therefore also located on intrinsic neurones of the spinal cord.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

RECENT studies have suggested that opiate addiction is associated with transcriptional changes. We developed a novel method,in situDNA-protein binding (ISDB), for investigating the distribution and changes of DNA binding activity of transcription factors in the brain. Using this method, we found that cAMP response element (CRE) binding activity was decreased by chronic morphine treatment in specific regions including the amygdala complex, thalamus, cerebral cortex and hypothalamus in mouse brain. This effect persisted for at least 14 days after the cessation of morphine. These data suggest that chronic morphine treatment elicits a long-term change in cAMP-mediated gene expression in the brain.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID

摘要:

THE effects of water deprivation or i.p. injection of hypertonic salt solution on the expression of the amyloid precursor polypeptide (APP) were studied immunohisto-chemically in the rat brain, in particular in the supraoptic and paraventricular nuclei, both known to be involved in electrolytic and water homeostasis and to contain mRNAs coding for the various forms of APP. In parallel, the expression of the immediate early gene c-foswas also studied by immunohistochemistry. Both hypertonic saline injection and water deprivation resulted in a rapid and dramatic increase in the levels of amyloid precursor protein-like immunoreactivity in neurones of the supraoptic and paraventricular nuclei. These increases paralleled those seen using c-fosimmunohistochemistry. In contrast, no changes were observed in other brain areas, including the subfornical organ, which also contained mRNA and APP-like immunoreactivity. The results indicate that levels of the β-amyloid precursor protein can be rapidly increased by stressors affecting the activity of well characterized cell populations in the rat hypothalamus. These results suggest the involvement of the β-amyloid precursor protein in the secretory activities of these cells, or in the initiation of morphological changes which are known to occur after osmotic stress in the supraoptic and paraventricular neurones. Interestingly, the changes were limited to neurones and no modification of β-amyloid precursor protein levels was observed in glial cells, which are also known to be modified by osmotic stress.

ISSN:0959-4965    

出版商:OVID    

年代:1995

数据来源: OVID