摘要:

A partial estrogen receptor beta (ER-β) cDNA was isolated from testicular quail RNA by RT-PCR with degenerate primers specific to the rat ER-β sequence. A high expression of ER-β was demonstrated by RT-PCR in the telencephalon, diencephalon, pituitary, testis and kidneys of male quail but little or no expression was detected in the cerebellum, pectoral muscle and adrenal gland.In situhybridization with a35S-labelled oligoprobe in sections through the preoptic area-rostral hypothalamus identified high expression in the medial preoptic nucleus, bed nucleus striae terminalis and nucleus taeniae. These data demonstrate the presence of an ER-β in brain areas implicated in the control of reproduction in a non-mammalian species.

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

REDOX factor-1 (Ref-1) is a dual-function protein involved in both DNA repair and transcriptional regulation. Ref-1 is modulated by cerebral ischemia and other oxidative stressors, and also regulates the DNA-binding activities of transcription factors implicated in Alzheimer's disease (AD)-related neurodegeneration. The present study examined Ref-1 expression in the AD hippocampus by immunohistochemistry. Although Ref-1 immunostaining was relatively low in control brain sections, senile plaques and other plaque-like structures in the AD brain were Ref-1-positive. Cells with increased Ref-1 immunoreactivity were also observed in regions of neuronal injury. These results suggest that Ref-1 might contribute to senile plaque formation, and that over-expression of Ref-1 in injured neurons may be part of a response to oxidative stress and an attempt to repair damaged DNA in AD.

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

THE ciliary ganglion of the chicken contains only two types of neurons. Using monoclonal antibodies against the α and the β subunits of Ca2+calmodulin-stimulated protein kinase II (CaMPK-II) we found that the α-subunit was localized to the choroid neurons while β subunit was associated with the ciliary neurons. As both neurons receive their inputs from the oculomotor nerve, while their postganglionic axons leave via different nerves, the ciliary ganglion of the chicken is a neuronal system in which the functional differences between α and β CaMPK-II homopolymers in the regulation of synaptic transmission can be investigated.

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

WE have recently shown that galactocerebroside (Gal-C)-expressing oligodendrocytes are highly vulnerable to (AMPA)/kainate receptor-mediated death. Here we examined the vulnerability of cells at different developmental stages of the oligodendrocyte lineage to AMPA/kainate receptor-mediated excitotoxicity. Oligodendrocyte precursor cells, pre-oligodendrocytes and mature oligodendrocytes were killed by 24 h exposures to low concentrations of kainate (30–100 μM). Death was attenuated by the AMPA/kainate receptor antagonist 6-nitro-7-sulfamoylbenzo(f)quinoxaline-2,3-dione (NBQX). The high vulnerability of oligodendrocytes and their precursors to AMPA/kainate receptor excitotoxicity may represent an important mechanism of white matter damage resulting from trauma or ischemia in the perinatal and adult central nervous system (CNS).

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

MALE rats were injected with 6-hydroxydopamine in the lateral hypothalamus and tested for ingestive behavior starting on the day after the injection. The rats did not eat food pellets but readily ingested an intraorally infused nutritive solution. If given three daily intraoral infusions, 6-hydroxydopamine-treated rats defended their body weight and were as sensitive to the inhibitory effect of cholecystokinin octapeptide on intake as controls. Dopamine was reduced by 94% in the dorsal striatum five days after the 6-hydroxydopamine injection. Noradrenaline and serotonin were less markedly affected. Thus, while appetitive ingestive behavior is disrupted, consummatory ingestive behavior and body weight regulatory competence are only marginally affected by massive damage to forebrain dopamine neural networks

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

THE P2 protein is a neuritogenic, small basic protein present in PNS myelin. It belongs to the family of the cytoplasmic lipid-binding proteins and can be incorporated in lipidic bilayers. P2 has been purified and crystallized only in the lipid-free form. Here we show that the P2 protein can be purified with bound lipids by applying to PNS myelin the same procedure that as used to purify lipid-bound myelin basic protein from CNS myelin. SDS-PAGE showed a single band of 16. 5 kDa, and TLC showed the presence of most of the myelin lipids associated with the protein. Lipid-bound P2 revealed different circular dichroism spectra from the corresponding lipid-free form, indicating that lipids influence P2 conformation

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

THE acute action of insulin on neurogenic flare was investigated using iontophoresis. Twenty-five patients with insulin-dependent diabetes mellitus (IDDM) and 25 age- and gender-matched controls were studied. Axon reflex vasodilatation was evoked by transdermal iontophoresis of acetylcholine (ACh) before and after skin treatment by the iontophoresis of insulin and measured using laser Doppler velocimetry. Axon reflex responses were reduced in IDDM patients compared with controls (p< 0.001) but were restored after the iontophoresis of insulin. Insulin iontophoresis had no effect on the size of the axon reflex response in control subjects (p< 0.05). This study confirms the reduction of the ACh-induced flare in human patients with IDDM and has demonstrated relatively rapid effects of insulin on this cutaneous neurogenic response.

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The parkinsonism-inducing neurotoxin 1-methyl-4-phenylpyridine (MPP+) acts through inhibition of complex I of the electron transport chain. Recent evidence suggests that it may also act through inhibition of 2-ketoglutarate dehydrogenase complex (KDHC). We confirmed this observation in isolated rat liver mitochondria but found that this inhibition is prevented by preincubation with the radical quencher, cysteine (Cys). KDHC is also inhibited by the NO generator S-nitroso-N-acetyl-penicillamine (SNAP) and this inhibition is similarly blocked bycysteine. MPP+may inhibit KDHC secondary through a radical-mediated event rather than through directinteraction with KDHC.

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

WE investigated whether glycinergic transmission develops organotypically in auditory brain stem cultures. Slices of the medial nucleus of the trapezoid body and the lateral superior olive were incubated in medium with a raised extracellular K+concentration. Asin vivo, glycine receptor α1 subunit immunoreactivity increased and became clustered on somata and proximal dendrites. Together with organotypic expression of glycine transporter GLYT2, this indicates that molecular components of glycinergic synapses form properly. In contrast, glycinergic synaptic currents did not develop asin vivo: after 7 daysin vitrothey were still similar to those at the time of culture preparation. We suggest that for organotypic development of glycine receptors and transporters, Ca2+influx due to elevated K+is sufficient. The development of functional synaptic transmission, however, may require patterned electrical activity.

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SPINAL motoneurons are highly vulnerable to kainate bothin vivoandin vitro. Tissue-type plasminogen activator (tPA) and plasmin have recently been shown to mediate kainate-induced neuronal death in the mouse hippocampusin vivo. The aim of the present study was to determine whether tPA also mediates the kainate-induced death of motoneuronsin vitro. A motoneuron-enriched neuronal population was isolated from the ventral spinal cord of wild-type (WT) and tPA–deficient (tPA–/–) mouse embryos. WT and tPA–/–neurons were cultured on WT and tPA–/–spinal glial feeder layers, respectively. WT and tPA–/–co-cultures were morphologically indistinguishable. Expression of tPA in WT co-cultures was demonstrated using RT-PCR. WT and tPA–/–co-cultures were exposed to kainate for 24 h. The neurotoxic effect of kainate did not differ significantly between WT and tPA–/–cultures. The plasmin inhibitor α2-antiplasmin did not protect WT neurons against kainate-induced injury. These results indicate that the plasmin systemis not a universal mediator of kainate-induced excitotoxicity.

ISSN:0959-4965    

出版商:OVID    

年代:1998

数据来源: OVID