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41.
Da-Nian Zhu, Long-Mei Xue, Peng Li. Effect of central muscarine receptor blockade. with DKJ-21 on the blood pressure and heart rote in stress-induced hypertensive rats.
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area. 相似文献
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43.
Replacement of cholesterol gallstones by murideoxycholyl taurine gallstones in prairie dogs fed murideoxycholic acid 总被引:1,自引:0,他引:1
B I Cohen N Ayyad E H Mosbach C K McSherry N Matoba A F Hofmann H T Ton-Nu Y Peng C D Schteingart R J Stenger 《Hepatology (Baltimore, Md.)》1991,14(1):158-168
The effect of two hydrophilic bile acids, murideoxycholic acid (3 alpha,6 beta-dihydroxy-5 beta-cholanoic acid) and ursodeoxycholic acid, on cholesterol and bile acid metabolism and hepatic pathology and gallstone composition was studied in the prairie dog. Cholesterol gallstones were induced by feeding a diet containing 1.2% cholesterol for 75 days. The animals were divided into six groups, and gallstone regression was studied as follows: groups 2 and 5, chow plus 0.2% cholesterol; groups 3 and 6, chow plus 0.2% cholesterol plus 0.15% ursodeoxycholic acid; groups 4 and 7, chow plus 0.2% cholesterol plus 0.15% murideoxycholic acid. Animals in groups 2 to 4 were killed after an additional 6 wk; animals in groups 5 to 7 were killed after an additional 12 wk. Gallstone dissolution did not occur in any group. The gallstones in groups 2, 3, 5 and 6 were typical cholesterol aggregates, as determined by polarized light microscopy and Fourier transform infrared spectrometry. The gallstones of the murideoxycholic acid group were large, solitary, dark stones that appeared radiopaque under 22 kVp x-ray examination. Scanning electron microscopy showed that in these stones the cholesterol crystals had been replaced by an amorphous material, both within the stone and on the stone surface. Chemical analysis indicated that at the end of 12 wk the calcium/sodium salt of the taurine conjugate of murideoxycholic acid (murideoxycholyl taurine) comprised 70% of the stones; protein, cholesterol and small amounts of other bile salts were also present. In vitro studies confirmed the insolubility of the sodium and calcium salts of murideoxycholyl taurine. These studies indicate that the hydrophilic bile acids, murideoxycholic acid and ursodeoxycholic acid, did not achieve gallstone dissolution under the conditions used. In the animals fed murideoxycholic acid, an insoluble calcium salt of murideoxycholyl taurine replaced cholesterol as the major constituent of gallbladder stones. This is the first example of an insoluble dihydroxy taurine-conjugated bile acid; administration of the unconjugated bile acid induced precipitation of a kind of gallstone not previously reported. The final result was transformation of cholesterol stones to bile salt stones. 相似文献
44.
30例肝硬化食管静脉曲张破裂大出血患者,用垂体后叶素0.2~0.4U/min连续静脉滴注和硝酸甘油含服联合治疗。结果表明,近期止血有效申达80%,死亡率10%;无一例出现严重心绞痛和心电图异常。 相似文献
45.
用PowerPoint XP设计幻灯片元素动画效果的实践 总被引:6,自引:1,他引:5
PowerPoint XP新特性中突出的就是其动画设计功能的加强。文中对新增加的与动画没计相关的功能使用要点结合实际作了较详细的叙述。 相似文献
46.
作者以ABEI-CoCl_2-H_2O_2作为化学发光指示系统,用固相竞争法检测58例白细胞减少症患者、41例无白细胞减少症患者及32例正常人等的粒细胞抗体IgG。判断标准采用正常人血清化学发光强度指数法。实验结果表明,白细胞减少症患者血清中粒细胞抗体阳性率明显高于无白细胞减少症患者(P<0.005)。本法敏感性为43.1%,特异性为90.2%,准确性为62.6%,是一种灵敏而准确的方法,能将粒细胞包被试管在室温下较长时间保存,以供临床监测粒细胞抗体,大大缩短检测时间。 相似文献
47.
48.
Ligustrazini in the treatment of chronic cor pulmonale 总被引:2,自引:0,他引:2
49.
50.
In this study antigen-independent factor in the pathogenesis of chronic rejection of organ transplants was examined.Kidney isografts and allografts were transplanted orthotopically into bilaterally nephroectomized rat recipients and studied functionaaly,morphologically and immunohistologically,at serial intervals up to 52 weeks after transplantation.Allograft recipients developed progressive proteinuria after 12 weeks,with gradual renal failure ultimately leading to death.At the same time,morphological changes,including progressive arteriosclerosis and glomerulosclerosis ,tubular atrophy and interstitial fibrosis,developed.Immunohistologically,macrophages infiltrated glomeruli during this period and cytokines became unregulated.Our results showed that antigen-independent functional and morphological changes occurred in long-tern kidney isografts and mimicked those appearing much earlier in allografts that reject chronically.Initial injury and extent of functioning renal mass is suggested to be important factor for such late changes. 相似文献