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1.
Spectral analysis of the electroencephalogram in neonatal rats chronically treated with the NMDA antagonist MK-801. 总被引:1,自引:0,他引:1
J A Gorter M Veerman M Mirmiran N P Bos M A Corner 《Brain research. Developmental brain research》1991,64(1-2):37-41
In order to study the involvement of NMDA-receptor activation in brain development, rat pups were chronically treated with the non-competitive NMDA antagonist MK-801 during the neonatal period. We recorded the cortical EEG at various vigilance states throughout the treatment period. Spectral analysis of the EEG showed reduced power in the delta (delta) frequency range (1.5-4 Hz) during quiet sleep and less power in the theta (theta) range (4-7 Hz) during REM-sleep in MK-801 animals than in controls. No significant differences were found for the total time spent in each of the different vigilance states. We conclude that chronic MK-801 treatment probably causes a developmental retardation in state-related brain activities. 相似文献
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Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells. 相似文献
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表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
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C. H. Polman C. J. A. de Groot J. C. Koetsier T. Sminia A. J. P. Veerman 《Journal of neurology》1987,234(1):19-22
Summary Determinations of mononuclear cell subsets in cerebrospinal fluid (CSF), using monoclonal antibodies against surface antigens which identified pan T-cells, helper/inducer T-cells, cytotoxic/suppressor T-cells and Ia-positive cells, were performed in patients with multiple sclerosis (MS), other neuroimmunological diseases (NID), infectious diseases (INF) of the central nervous system and with other neurological diseases. Whereas there was an elevated helper T/suppressor T ratio in CSF of patients with NID (Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, cerebral vasculitis), no other significant differences could be detected between the different groups of patients. Our results suggest that analysis of these mononuclear cell subsets in CSF is not helpful in discriminating between MS and other neurological diseases and that in MS patients changes in disease activity are not clearly indicated by fluctuations in the different CSF cell subsets. Further studies will be needed to confirm our findings in NID patients and to understand the diagnostic and theoretical implications. 相似文献
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Long-lasting effects of neonatal interference with N-methyl-D-aspartate (NMDA) receptors were investigated by measuring responses to micro-iontophoretically applied NMDA agonists/antagonist in hippocampal neurons of the adult rat. Rat pups were chronically treated with MK-801 from postnatal day 8 through 19 and tested at postnatal day 70-100. CA1 cell responses to glutamate were not affected by the neonatal treatment. However, a stronger suppression of the NMDA evoked response by the NMDA site antagonist amino-5-phosphonovalerate (APV) was measured, suggesting a long-lasting configurational change of the NMDA receptor. The NMDA evoked responses were equally strong suppressed by MK-801 in both groups, suggesting that channel sites were not affected by this treatment. 相似文献