山菍不同提取物对正常动物颈总动脉血压影响的比较研究

目的比较研究山菍3种提取物对正常动物颈总动脉血压的影响。方法以水提醇沉法分离得山菍总提物、纯化物和沉淀物;用正常猫、犬急性降血压实验,比较3种提取物对颈总动脉血压的影响。结果山菍总提物和纯化物经十二指肠灌注给药,能使颈总动脉血压下降20%以上。结论山菍水溶性提取物对正常动物血压有降压作用。

两种植物提取物对家兔颈总动脉血压影响的比较研究

以家兔为研究对象,探讨两色金鸡菊和芳香新塔花两种提取物对家兔颈总动脉血压、心率的影响,并比较其异同。试验将两色金鸡菊和芳香新塔花提取物各设低、中、高3个浓度组,采用生物信号系统采集、记录家兔颈总动脉血压,比较加药后各组家兔舒张压、收缩压和心率的变化。结果表明:两色金鸡菊和芳香新塔花提取物3个浓度组均能使家兔颈总动脉收缩压、舒张压明显下降,二种提取物对舒张压的影响比对收缩压的影响更明显,但对心率抑制影响并不明显。与芳香新塔花提取物相比,同剂量的两色金鸡菊提取物对家兔颈总动脉血压抑制更为明显。说明两色金鸡菊提取物比芳香新塔花提取物有更强的降血压作用。

急性右心衰竭兔中心静脉压及颈总动脉压与肠系膜微循环的关系

目的 探讨急性右心衰竭时肠系膜微循环的改变。方法 利用液体石蜡栓塞家兔肺循环毛细血管 ,快速大量输液 ,复制家兔急性右心衰模型。观察记录中心静脉压、颈总动脉压及肠系膜微循环的变化 ,并分析两者之间的相关性。结果 随着急性右心衰竭的进展 ,中心静脉压愈高及颈总动脉压愈低 ,微循环血管袢数、输入支和输出支管径、输入支和输出支流速均减小 (p <0 .0 5 )。结论 心脏后负荷增高 ,微循环趋于“缺血状态” ;前负荷增高 ,微循环出现“淤血性”改变。

失重对脑血流影响的仿真研究

目的应用计算机仿真探讨失重对脑血流的影响。方法根据流体力学参数与电学变量等效的原理,利用Pspice语言建立人体心血管系统模型,包括人体心脏模型、动脉系统模型、静脉系统模型以及外周血管模型等四部分。仿真了0G与1G下脑血流、颈动脉血压与主动脉弓血压的变化曲线。结果0G时脑血流量比1G时增加10%左右,颈动脉血压比1G时增高10mmHg。结论本模型可以较好地模拟失重条件下脑血流的变化,为进一步研究失重对脑血流的影响提供了新方法。

大鼠羊水栓塞时的内皮素-1的含量及其作用的研究

[目的]利用放射免疫(RIA)法测定羊水栓塞(AFE)大鼠模型血及肺组织中的内皮素I(ET-1)的含量。进一步探讨羊水栓塞的发病机机制,为寻找新的治疗方法提供理论基础。[方法]取SD雌性未孕大鼠60只,随机分成6组,每组各10只,羊水分别取自足月妊娠胎粪污染组、原羊水组、上清液组,20妊娠周组,生理盐水对照组①及未经注入任何液体的对照组②。[结果]胎粪液组、原羊水组及上清羊水组ET-1的水平与对照组存在着显著的差异,胎粪组血清ET-1水平为147.79PG/mL,上清液组为83.98PG/mL。20妊娠周羊水组ET-1水平与对照组间无显著差异。[结论]内皮素与羊水栓塞的发生存在着密切关系。内皮素随着羊水栓塞病情的加重而增高,呈正相关。

Association between serum homocysteine and arterial stiffness：role of anti-hypertensive drugs

To the Editor I read the article of Zhang, et al. with great interest. They investigated the association of homocysteine with arterial stiffness in Chinese community-based elderly persons. The carotid-femoral pulse wave velocity （PWV） was significantly higher in the high homocyteine group than in the normal one, however, there was no differences in carotid-radial PWV between the high homocyteine group and the normal one. Homocysteine levels were strongly associated with the carotidfemoral PWV even after adjustment for classical risk factors of cardiovascular disease. I congratulate the authors for this important study. However, I want to make minor criticism for this study from the methodological aspect.

Role of TGF-β1/Smads pathway in carotid artery remodeling in renovascular hypertensive rats and prevention by Enalapril and Amlodipine

Objective To investigate the role of transforming growth factor-β1 （TGF-β1）, Smad2/3 and Smad7 expressions in carotid artery remodeling in renovascular hypertensive rats, and also the therapeutic effect of Enalapril and Amlodipine. Methods The renovascular hypertensive rat （RHR） models with ＂two-kidney and one-clip＂ were established, including model group （n = 6）, sham-operated group （n = 6）, Enalapril group （10 mg/kg per day, n = 6）, Amlodipine group （5 mg/kg per day, n = 6） and combination group （Amlodipine 2.5 mg/kg per day ＋ Enalapril 5mg/kg per day, n = 6）. The medication were continuous administrated for six weeks. Carotid artery morphological and structural changes in the media were observed by HE staining, Masson staining and immuno histochemical staining. Media thickness （MT）, MT and lumen diameter ratio （MT/LD）, and the expression levels of media a-smooth muscle actin （α-actin）, proliferating cell nuclear antigen （PCNA）, TGF-β1, phosphorylated Smad2/3 （p-Smad2/3） and Smad7 in carotid arteries were measured. Results The media of carotid arteries in RHR model group was significantly thickened, the volume of smooth muscle cell was increased, and the array was in disorder; MT, MT/LD, the proliferation index of smooth muscle cell and collagen fiber area percentage of carotid arteries in the model group were significantly higher than those in the sham-operated group （P 〈 0.01）. Compared to sham-operated group, the model group had significantly higher expressions of TGF-β1 and p-Smad2/3 （P 〈 0.05） and lower Smad7 expression. Both Enalapril and Amlodipine improved smooth muscle hypertrophy and collagen deposition, reduced RHR carotid MT, MT/LD, proliferation index of smooth muscle cell, collagen fiber area percentage and the expressions of TGF-β1 and p-Smad2/3 （P 〈 0.05）, increased Smad7 expression （P 〈 0.05）. Moreover, the combination treatment of Enalapril and Amlodipine had significantly better effects than single Amlodipine group （P 〈 0.05）, but not single Enalapril group. Conclusions TGF-β1/Smads pathway may participate in the mechanism of carotid artery remodeling in RHR; the role of Amlodipine and Enalapril in inversing carotid artery remodeling may be related to the change of TGF-β1/Smads pathway, the combination treatment of Amlodipine and Enalapril had better effects than single administration of Amlodipine.