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11.
D. F. Wozniak J. W. Olney L. Kettinger III M. Price J. P. Miller 《Psychopharmacology》1990,101(1):47-56
Several experiments were conducted to study the effects of the noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, on learning and memory in the rat. Rats displayed impaired performance on several sensorimotor tests and appeared grossly intoxicated when treated IP with 0.2 mg/kg MK-801, but not when treated with lower doses (0.05 or 0.1 mg/kg). Postacquisition performance on two spatial learning tasks involving working memory protocols (reinforced alternation and radial arm maze) was impaired by MK-801 at intoxicating doses (0.2 mg/kg) but not at lower doses (0.05 or 0.1 mg/kg). Using a position habit reversal task, we found that rats could learn to reverse a position habit while under the influence of a nonintoxicating dose of MK-801 (0.1 mg/kg), but when tested on the following day performed as if they did not recall what they had learned. Thus, acute administration of a nonintoxicating dose of MK-801 disrupts the retention of new information learned under the influence of the drug but does not interfere with the performance of tasks that are well learned before the drug is administered. Whether the performance deficits on the spatial learning tasks observed only following intoxicating doses of MK-801 reflect an effect on memory is not clear. 相似文献
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13.
D.F. Wozniak G. Brosnan-Watters A. Nardi M. McEwen T.D. Corso J.W. Olney A.S. Fix 《Brain research》1996,707(2):165
Several histological and behavioral experiments were conducted to investigate the neurotoxic effects of MK-801 in male mice. Moderate subcutaneous (s.c.) doses of MK-801 (0.5 and 1.0 mg/kg) induced the formation of intracytoplasmic vacuoles in pyramidal neurons in layers III and IV of the posterior cingulate/retrosplenial (PC/RS) cortex in 50% and 100% of the mice from the two respective treatment groups. Electron microscopic analysis of the vacuoles indicated that mitochondria and endoplasmic reticulum are the cellular organelles most prominently involved in this pathomorphological change. Treating mice with a high systemic dose of MK-801 (10 mg/kg s.c. or intraperitoneal (i.p.)) caused selective, irreversible degeneration of a small number of PC/RS cortical neurons. Compared to saline controls, the acquisition performance of mice treated i.p. with 10 mg/kg MK-801 was chronically impaired on a spatial learning task (modified hole board food search task) when tested at several posttreatment intervals (up to at least 5 months), although the groups did not differ on activity or sensorimotor tests conducted 2 weeks posttreatment. In summary, MK-801 caused histopathological changes in the mouse brain similar to those observed in the rat. Furthermore, high dose MK-801 treatment that killed a small number of mouse PC/RS cortical neurons resulted in a chronic acquisition impairment in spatial learning, an effect not previously demonstrated in any species. 相似文献
14.
A. Svensson M. Carlsson A. Carlsson 《Journal of neural transmission (Vienna, Austria : 1996)》1991,85(1):69-77
Summary When administered to mice pretreated with the monoamine-depleter reserpine and the catecholamine synthesis inhibitor -methyl-para-tyrosine, the preferential autoreceptor antagonists (+)-AJ 76 and (+)-UH 232 induced weak locomotor stimulation. When either (+)-AJ 76 or (+)-UH 232 was combined with a subthreshold dose of the selective NMDA antagonist dizocilpine (MK-801), a marked locomotor stimulation was produced in monoamine-depleted mice. The mechanism of this stimulation, although reduced by dopamine antagonists, remains to be clarified. 相似文献
15.
用HPLC法测定马来酸依那普利片的含量和有关物质 总被引:3,自引:0,他引:3
目的:采用改进的HPLC法测定马来酸依那普利片中马来酸依那普利和有关物质的含量。方法:采用HypersilBDS C8色谱柱(250 mm×4.0 mm,5μm ID);0.001 mol/L磷酸二氢铵溶液(用磷酸调节pH值至2.0)-甲醇(60:40);检测波长215 nm。结果:马来酸依那普利在0.1~0.3 mg/ml范围内线性关系良好(r=0.999 9);方法的平均回收率为99.8%。依那普利与有关物质之间分离良好。结论:本法有较高的回收率、精密度和重现性。 相似文献
16.
咳特灵胶囊中马来酸氯苯那敏的高效毛细管电泳-电导法测定 总被引:3,自引:0,他引:3
建立了咳特灵胶囊中马来酸氯苯那敏含量的高效毛细管电泳 -电导测定法。采用未涂层弹性融硅石英毛细管柱 (4 0 cm× 75 μm) ,1× 10 -3 mol/L Na2 HPO4溶液为电泳介质 ,重力方式进样 ,室温下 15 k V恒压电泳分离 ,电导检测。马来酸氯苯那敏在 9.8~ 117.6μg/ml浓度范围内线性关系良好 ,平均回收率 96.8% ,RSD为 1.9%。 相似文献
17.
目的为了控制咳特灵胶囊(片)的质量,建立马来酸氯苯那敏的含量测定方法.方法HPLC测定马来酸氯苯那敏的含量,用Kromasil C18柱,流动相为乙腈-3%冰乙酸-三乙胺(20800.08),醋酸调节pH=3.0;检测波长262 nm;流速1.5 ml/min.结果马来酸氯苯那敏在81~408μg范围内线性关系良好(r=0.9999),平均回收率为98.1%.RSD=0.67%.结论本法方便、快速、准确、可作为咳特灵胶囊(片)的质量控制. 相似文献
18.
复方制剂珮夫人小儿咳露中主药成分的含量测定 总被引:2,自引:0,他引:2
目的 :建立一种采用高效液相色谱检测复方制剂中氢溴酸美沙芬、愈创木酚甘油醚和马来酸氯苯那敏含量的方法。方法 :采用C1 8色谱柱 ,以 0 .0 0 2 5mol·L- 1 IPR -B6 甲醇溶液∶水 (含 2 %三乙胺 )∶磷酸 (12 0∶10 0∶1)为流动相 ,检测波长为 2 5 7nm。结果 :氢溴酸美沙芬、愈创木酚甘油醚和马来酸氯苯那敏 3种成分的回收率分别为10 0 .5 % ,99.5 % ,10 0 .6% ;RSD分别为 2 .2 % ,1.6% ,1.9% (n =7)。结论 :本方法简便 ,结果准确可靠 相似文献
19.
Facilitating effect of histamine on spatial memory deficits induced by dizocilpine as evaluated by 8-arm radial maze in SD rats 总被引:3,自引:3,他引:3
HUANG Yu-Wen CHEN Zhong~ HU Wei-Wei ZHANG Li-San WU Wei YING Li-Yang WEI Er-Qing Department of Neurobiology Pharmacology School of Medicine Zhejiang University Hangzhou China 《Acta pharmacologica Sinica》2003,(12)
AIM: To investigate whether or not histamine is involved in spatial memory deficits induced by dizocilpine (MK-801) as evaluated by 8-arm radial maze of rats. METHODS: 8-Arm (4-arm baited) radial maze was used to measure spatial memory in rats. RESULTS: Bilaterally intrahippocampal (ih) injection of MK-801 (0.3 μg/site) impaired working memory and reference memory in rats. Both histamine (50, 100 ng/site, ih) and intraperitoneal (ip) injection of histidine (100, 200 mg/kg) markedly improved the spatial memory deficits induced by MK-801. On the other hand, the ameliorating effect of histidine (100 mg/kg, ip) was completely antagonized by α-fluoromethylhistidine (α-FMH, 5 μg/site, ih), a potent and selective histidine decarboxylase (HDC) inhibitor, and H_1-antagonist pyrilamine (1 μg/site, ih), but not by H_2-antagonist cimetidine, even at a high dose (2.5 μg/site, ih). CONCLUSION: The hippocampal histamine plays an important role in the ameliorating effect on MK-801-induced spatial memory deficits, 相似文献
20.
目的:建立一种测定马来酸替加色罗片剂的含量及有关物质的HPLC方法,并对马来酸替加色罗片剂的稳定性进行初步研究。方法:使用Agilent 1100型高效液相色谱仪,色谱柱为Diamonsil(钻石)C18 150 mm×4.6mm(5μm),流动相为乙腈-1%十二烷基硫酸钠缓冲溶液(含0.95%冰醋酸)(56:44),检测波长为314 nm,流速:1 mL·min-1(有关物质考察),或2 mL·min-1(含量测定),柱温:40℃。结果:本法测定马来酸替加色罗在0.0001-0.12 mg·mL-1的范围内线性良好,线性方程为A=28.93C-14.46(r=0.9999,n=6);日内精密度RSD<1.1%;日间精密度RSD<3.1%;高、中、低浓度的平均加样回收率在100.4%-103.8%之间;定量限为4.08 ng(S/N=10)。结论:本方法检测马来酸替加色罗及其有关物质,专属性强,灵敏度高,重现性好。稳定性研究结果表明,马来酸替加色罗片剂应被储存于干燥、阴凉的环境中。 相似文献