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71.
黑质内注射FeCl3对大鼠纹状体多巴胺释放量及含量的影响 总被引:3,自引:3,他引:0
①目的探讨黑质(SN)内注射不同剂量的FeCl3对大鼠纹状体(CPu)多巴胺(DA)释放量和含量的影响.②方法实验用SD大鼠32只,分成4组6只大鼠为正常对照组;9只大鼠左侧SN内注射 FeCl3溶液10 μg(Ⅰ组);8只大鼠左侧SN内注射FeCl3溶液20 μg(Ⅱ组);9只大鼠左侧SN内注射FeCl3溶液40 μg(Ⅲ组),3周后采用快速周期伏安法(FCV)监测纹状体D A的释放量,高效液相色谱法(HPLC)检测纹状体DA含量.③结果在FeCl3单侧损毁大鼠中,损毁侧CPu DA释放量的减少和DA含量的降低与注射FeCl3剂量之间有明显剂量依赖关系(F=93.78,164.51,q=3.50~29.79,P<0.05).Ⅲ组损毁侧CP u DA的更新率[以(DOPAC+HVA)/DA表示]明显加快,与其他组比较差异有显著性(F=13 6.22,q=22.32~22.72,P<0.05);而Ⅰ,Ⅱ组变化较小,与正常大鼠相比差别无统计学意义 (q=0.25,2.04,P>0.05).④结论黑质内Fe3+含量升高可使CPu内DA释放量和含量均降低,铁含量高可能参与帕金森病的病理改变. 相似文献
72.
73.
目的 :探讨奶茶对大鼠体重和血清胆固醇含量的影响。方法 :将大鼠随机分为对照、脂对照、奶、茶和奶茶五组 ;高脂饲养的同时分别用水、奶、茶和奶茶进行灌胃 ,定期测定大鼠的血清胆固醇 (TC)。结果 :实验期间奶茶组大鼠体重的增长量高于其他三个高脂饲料组 ,且明显高于对照组 (P <0 .0 5 ) ;高脂饲料组大鼠的血清胆固醇含量明显增加 ,但增长量在高脂饲料组间差异无显著性 (P >0 .0 5 )。结论 :本实验浓度的奶茶对高脂饲料诱导的大鼠血清胆固醇升高未见有降低作用 相似文献
74.
E. V. Borisova D. Yu. Rusakov S. K. Sudakov 《Bulletin of experimental biology and medicine》1992,114(3):1328-1332
75.
D. Dickerson B. Adams G. Engelbrecht G. Boltman R. Hickman D. Kahn 《Transplant international》1992,5(Z1):S63-S64
The precise cause of allograft dysfunction after renal transplantation often cannot be established by non-invasive means. In clinical practice, radionuclide scans form an integral part of the clinician's armamentarium in the assessment of these patients [1, 2]. Unfortunately, in the clinical setting more than one pathological process may be responsible for the impaired function, making it difficult to correlate the scan appearances with the pathology. In this study in rats we compared the renal DTPA scan appearances of the various pathological processes which may cause renal allograft dysfunction in the immediate post-transplant period. 相似文献
76.
Chronic food restriction has been shown to enhance glucose metabolism in adipocytes from lean Zucker rats at 10, 26, and 52 weeks of age compared to ad libitum-fed lean rats. Only adipocytes from food restricted 10-week-old obese rats demonstrated this response. In this study, lean and obese rats were food restricted from 5 until 14 weeks of age to determine the age at which adipocytes from obese rats were no longer affected by this intervention. Effects of 1 week of refeeding were also determined. When the rats were killed, body weights were highest in control rats followed by restricted/refed and then restricted rats within each genotype. Epididymal pad weights of lean rats were resistant to dietary intervention, while those of obese-restricted and obese-restricted/refed rats weighed less than pads of obese-control rats. Retroperitoneal pad weight was lowered by food restriction in both genotypes; but only that of lean-restricted/refed rats totally recovered with refeeding. Adipocytes of lean-restricted rats had the highest conversion of glucose to CO2. Glyceride-glycerol production was higher in obese compared to lean rats, but restricted rats had elevated conversion of glucose to fatty acids. In general, these results indicate that by 14 weeks of age obese Zucker rats no longer respond to food restriction with an elevated rate of glucose metabolism in adipocytes. 相似文献
77.
一种改良大鼠异体肾移植模型的建立 总被引:8,自引:6,他引:2
目的:为开展器官移植的实验研究,建立大鼠异体肾移植模型。方法:用SD大鼠作为供体和受体,采用原位低温灌注,原位修剪,移植肾放置左侧,血管直接吻合,输尿管带膀胱瓣与膀胱吻合。结果:经过60次的实验,克服了移植物灌注、血管吻合、膀胱吻合等技术难关,建立了稳定实用的肾移植动物模型。手术成功率为80%左右。结论:此模型可以在一般的实验室条件下开展。有较高的成功率,符合肾移植实验研究的需要。 相似文献
78.
79.
P. M. TIIDUS S. ZAJCHOWSKI D. ENNS D. HOLDEN E. BOMBARDIER A. N. BELCASTRO 《Acta physiologica (Oxford, England)》2002,174(2):131-136
The effects of oestrogen administration on 1 h post‐exercise cardiac muscle myeloperoxidase (MPO) and calpain activities were determined in female rats. Rats were ovariectomized and implanted for 2 weeks with either oestrogen (25 mg 17‐oestradiol) or placebo pellets or left with ovaries intact. Rats were then run for 1 h at 21 m min–1, 12% grade, killed 1 h post‐exercise and cardiac muscle and blood samples were removed. Control animals from each group were killed without prior exercise. Serum oestrogen levels in the order of the highest to lowest were; ovariectomized oestrogen replaced rats > intact ovaries rats > ovariectomized placebo rats. Oestrogen induced significant (P < 0.05) elevations in cardiac MPO activity at rest and at 1 h post‐exercise in ovariectomized rats. No significant elevations in cardiac MPO activity were evident in placebo ovariectomized or normal ovary rats at rest or post‐exercise. Cardiac calpain activities were similar in all unexercised groups. Ovariectomized placebo and intact ovary rats had significantly (P < 0.05) elevated cardiac calpain activities 1 h post‐exercise while calpain activity was not significantly elevated in hearts from ovariectomized oestrogen rats. These results demonstrate that oestrogen supplementation in ovariectomized rats induces elevations in cardiac muscle MPO activities at rest and at 1 h post‐exercise. This is opposite to the effect of oestrogen in post‐exercise skeletal muscle and implies a greater neutrophil infiltration into cardiac muscle caused by oestrogen. This effect cannot be explained by changes in 1 h post‐exercise cardiac muscle calpain activity, the elevation of which was suppressed by oestrogen administration. Oestrogen influences cardiac calpain activity similarly to its effect in skeletal muscle. Thus, oestrogen administration to ovariectomized rats induces elevations in cardiac MPO activity while suppressing cardiac calpain activity. 相似文献
80.
本文观察了CS_2对大鼠胚胎发育及血清锌、铜含量的影响。发现胚胎着床前死亡率升高,胎鼠皮下出血、心包淤血及骨骼骨化不金的发生率增高。但无明显的致畸效应。14.1及103.9ng/m~3的CS_2对妊娠大鼠的血清锌、铜含量无明显影响。说明CS_2对大鼠的胚胎毒性与其对妊娠大鼠血清锌、铜含量的影响之间没有关联。 相似文献