人升主动脉-主动脉弓的几何形态与显微结构

目的 为主动脉弓生物力学和血流动力学研究提供开矿学基础。方法应用组织学和计算机图像分析方法,对５例正常成人升主动脉－主动脉弓进行计量形态学研究。结果 获得了人升主动脉－主动脉弓几何形态和显微结构成分含量沿轴向和周向连续变化的完整数据。升主动脉根部结构成分以胶原纤维为主,左、右、后瓣环、窦壁的厚度和结构成分含量在血管财向无显著差异。结论 人主动脉弓几何形态与结构存在纤维和平滑肌显著,与其力学性质相符     

小鼠主动脉发生的观察

应用醛复红ＨＥ染色方法，对胎龄炒９、１１、１３、１５、１７、１９ｄ（新生）的小鼠主动脉的发生过程进行了较系统地观察。结果显示，在９ｄ胎龄的小鼠，其主动脉由一层内皮细胞组成，随着胎龄的增加，动脉壁逐渐增厚，依次出现间充质细胞，平均滑肌细胞和弹性张，而形成具有内、中、外膜结构的主动脉。     

实验性低血压大鼠腹主动脉的形态结构重建

目的研究低血压状态下腹主动脉重建的规律,探讨腹主动脉的应力生长关系。方法在大鼠在肾动脉起点以下缩窄腹主动脉,建立实验性低血压大民模型,按不同的时相点,在血管组织切片上,观察腹主动脉的几何形态指标及其显微结构成份的变化。结果低血压导致腹主动脉几何形态、平滑肌、胶原纤维及弹性纤维呈“负增长”状态。结论腹主动脉壁面积减小出现早,趋势最稳定,且在各个时相点之间“负增长”率及总“负增长”幅度最大,是低血压大鼠动脉重建的特征性几何形态学指标。在血管三种显微结构成分中,平滑肌对应力的反应最敏感,总“负增长”幅度最大,是影响腹主动脉重建的主要因素。     

主动脉弓的几何形态与显微结构

主动脉弓是一段几何形态和显微结构非常复杂的管道系统，血管的几何形态和显微结构决定了它的力学性质和血流动力学特点。在生长、衰老和疾病的过程中，血管均发生重建。血管结构的重建必然导致其生物力学性质和血流动力学特点的改变。本文针对主动脉弓的几何形态、显微结构以及在生长、衰老和疾病过程中，主动脉弓重建的特点进行综述。     

血管整形术中受力血管平滑肌细胞形态变化的实验研究

用生物软组织力学实验机对Ｗｉｓｔａｒ大鼠胸主动脉施行加压，在光、电镜下，观测不同受力状态下血管横，纵断面上主动脉壁中膜平滑肌细胞的形态变化，结果显示，受力血管平滑肌细胞及其核变长，长宽比增加，近外膜部平滑肌细胞受力的影响最明显。本结合血管整形术，对力与平滑肌细胞形态的影响，主动脉整形术后血管重新狭窄的结果变化特征等问题进行了讨论。     

三维培养的主动脉平滑肌细胞-胶原凝胶皮下移植的研究

目的 研究经三维培养后的主动脉平滑肌细胞(ASMC)-胶原凝胶移植后,是否仍能产生弹性纤维及宿主的接受状态。方法 将仿真皮替代物三维培养2周的ASMC-胶原凝胶植人大鼠皮下,分别于术后4、7、10、14和28d取材,用HE染色、Gomori醛复红染色、α肌动蛋白免疫组织化学染色和弹性蛋白免疫组织化学染色,观察和检测ASMC-胶原凝胶。结果在移植后第1周有大量的弹性纤维产生,但于28d时完全消失。在移植后的28d内,ASMC-胶原凝胶块周围没有明显的白细胞浸润。结论利用ASMC-胶原凝胶作为一种有弹性的真皮替代物,尚需讲一步的研究。     

人与猪胆总管几何形态和顺应性的比较

目的 探讨人与猪胆总管几何形态及顺应性的关系,为猪到人异种肝移植提供理论依据. 方法 取5例成年人尸体和50例3～12月龄湖北白猪的胆总管,在软组织生物力学实验机上测定胆总管的压力-直径关系.计算出顺应性.横断取材,冷冻切片,HE染色,用计算机图像分析系统测量其管径和管壁厚度. 结果 3～6月龄猪胆总管的管壁比成人的薄,其直径比成人的小(P<0.01),7～10月龄猪胆总管的壁厚和直径与成人的相近(P>0.05).3～6月龄及11、12月龄猪胆总管的顺应性明显小于成人(P<0.01),7～10月龄猪胆总管的顺应性与成人的相近(P>0.05). 结论 7～10月龄猪胆总管的几何形态和顺应性与成人的相近,从生物力学方面考虑,7～10月龄的猪肝作为人异种移植肝供源是可能的.     

主动脉平滑肌细胞在三维培养中产生弹性纤维的研究

目的 研究主动脉平滑肌细胞(ASMC)在仿真皮替代物的三维培养中是否能产生弹性纤维。方法 取1周龄SD大鼠胸主动脉,进行原代和传代培养,以α肌动蛋白免疫细胞化学染色鉴定平滑肌细胞。然后,将ASMC与胶原、甲壳素及糖胺多糖组合形成的凝胶混合,进行三维培养;培养1周和2周后,用Gomori醛复红染色和弹性蛋白免疫细胞化学染色,检测ASMC胶原凝胶。结果传代细胞经α肌动蛋白免疫细胞化学染色鉴定,98％以上为ASMC。培养1周和2周的ASMC胶原凝胶中,均显示有弹性纤维存在。结论 ASMC在仿真皮替代物的三维培养中能够产生弹性蛋白,并形成弹性纤维。     

人和猪升主动脉、肺动脉干的形态学和生物力学特性的比较研究概况

动脉是一个弹性体 ,动脉的力学特性与形态、结构和功能密切相关。本文针对猪在异种心脏移植研究中的应用 ,分别综述了人和猪的升主动脉和肺动脉干的几何性状、显微结构成份和生物力学特性及其比较研究的根况。提出对人和猪主动脉、肺动脉的形态学和生物力学特性进行深入、详实的比较研究对指导心脏异种移植的基础研究和未来的临床实践也是至关重要和不可缺少的     

升主动脉缩窄鼠升主动脉瘤的扫描电镜观察

目的：观察升主动脉缩窄鼠升主动脉瘤的形态特征，为动脉瘤的临床和实验研究提供资料。方法：以幼年wistar大鼠制作升主动脉缩窄鼠动脉瘤模型，取出动脉瘤，用扫描电镜观察。结果：动脉瘤的弹力板出现肥大、断裂，弹力板间的弹力纤维广泛破坏；动脉瘤壁中有炎性细胞浸润；平滑肌细胞大部分萎缩或消失；动脉瘤内皮严重受损，部分动脉瘤壁中有红细胞浸润。结论：动脉瘤存在超微结构的改变，提示以上形态学改变是动脉瘤发生的重要病理学基础。     

Spontaneous rupture of non-aneurysmal ascending aorta

Two autopsy cases with pericardial tamponade and spontaneous rupture of non-aneurysmal ascendlng aorta are described. In case 1, no apparent predisposing factor was clinically noticed in a 74 year old male patient, but postmortem examination revealed laceration of the ascending aorta associated with aortic valvular deformity and slight dilatation of the ascending aorta. In case 2, a 61 year old man, a mild to moderate grade of aortic regurgitation was noticed clinically 5 months before death. Postmortem examination revealed a slight dilatation of the aortic annulus and post-valvular portion of the ascending aorta. These two cases emphasize the clinical significance of aortic valvular disease with subsequent disordered blood flow, even when asymp tomatic, as a potential causative factor for spontaneous rupture of the ascending aorta.     

Cellular polymorphism in the myointimal thickening of the rabbit aorta

Research Institute of Experimental Cardiology, All-Union Cardiologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. Ivanovo Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR D. S. Sarkisov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 2, pp. 206–208, February, 1991.     

人与猪升主动脉、肺动脉干零应力状态的比较研究

目的 :比较人与猪升主动脉、肺动脉干零应力状态。方法 :取 5例人和 42例不同月龄猪的升主动脉、肺动脉干 ,沿其轴向均分为 5个等长的血管环 ,再沿径向剪开各血管环 ,2 0min后由计算机记录并测量各血管环的零应力状态张开角。结果 :人升主动脉的张开角从近侧端的 10 0 .4°± 12 .8°增至远侧端的15 2 .8°± 18.6° ,各月龄猪升主动脉张开角从近侧端的 68°左右增至远侧端的 13 0°左右 ;人肺动脉干张开角沿轴向无明显变化 ,各月龄猪肺动脉干的张开角从近侧端的 65°左右增至远侧端的 12 5°左右 ,猪升主动脉、肺动脉干的张开角不随年龄增加而发生显著变化。结论 :人和猪升主动脉、肺动脉干零应力状态张开角存在一定差异 (P <0 .0 5 ) ,但在某些区段二者相应动脉的张开角相近 ;猪受试血管的张开角无明显年龄性变化 (P >0 .0 5 )。     

Contractile response of normotensive rat aorta to serum from salt-loaded Sprague-Dawley rats

Sprague-Dawley rats were made hypertensive by 6-week dietary salt loading with 8% NaCl in the diet and compared with control rats which had normal feed and water. At the end of this period, the salt-loaded group developed hypertension but the heart rate did not differ significantly from control.Serum taken from salt-loaded rats showed enhanced vasoconstrictor effect on normal rat's aorta when compared with controls. This enhanced vasoconstrictor effect was attenuated by adrenergic receptor blockers but not by serotoninergic blockers. Thus salt loading may induce accumulation of vasoactive agents in the blood of rats.     

Sclerotomal origin of smooth muscle cells in the wall of the avian dorsal aorta.

The dorsal aorta is the earliest formed intraembryonic blood vessel. It is composed of an inner lining consisting of endothelial cells and an outer wall consisting of smooth muscle cells (SMCs) and fibrocytes. Aortic SMCs have been suggested to arise from several developmental lineages. Cephalic neural crest provides SMCs of the proximal part of the aorta, and SMCs of the distal part are derived from the paraxial mesoderm. Here, we show by using quail-chick chimerization that in the avian embryo, SMCs in the wall of the dorsal aorta at trunk level arise from the sclerotome. Our findings indicate a two-step process of aortic wall formation. First, non-paraxial mesoderm-derived mural cells accumulate at the floor of the aorta. We refer to these cells as primary SMCs. Second, SMCs from the sclerotome are recruited to the roof and sides of the aorta, eventually replacing the primary SMCs in the aortic floor.     

Reduced embryonic blood flow impacts extracellular matrix deposition in the maturing aorta

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Influence of exogenous substrates on adenosinetriphosphate (ATP) concentration in normal and diabetic rat aorta in vitro

In diabetic rat aorta glucose metabolism is impaired and changes in the activities of several enzymes are found. The aim of this study was to investigate whether the metabolic alterations in diabetic vascular tissue influence energy production. Aortas of normal and diabetic male Sprague-Dawley rats were incubated in vitro for up to 120 min with various substrates added to the incubation medium. Diabetes was induced by streptozotocin and the rats were used after a diabetes duration of two weeks. When normal and diabetic aorta were incubated in the presence of 5.6 mmol/1 glucose no significant difference in ATP-concentration was found after 60 min while after 120 min the ATP-concentration was lowered in diabetic aorta. Addition to the incubation medium of a substrate mixture containing amino acids in the same concentrations as in rat plasma, 3 mmol/1 DL-β-hydroxybutyrate and 1.5 mmol/1 palmitate increased the ATP-concentration, measured after 120 min, in diabetic aorta but not in normal aorta. No significant difference in ATP-concentration was found between normal and diabetic aorta incubated in a medium containing all substrates. When diabetic aorta was incubated with each substrate separately β-hydroxybutyrate but not glucose, palmitate or amino acids, increased the ATP-concentration to about the same level as the complete substrate mixture. The results suggest that the ability to utilize glucose for ATP production is impaired in diabetic vascular tissue and that other substrates such as ketone bodies are of importance for energy production in diabetic vessels.     

Age-related changes in the redox status of rat muscle cells and their role in enzyme-aging

The redox status of three biological components capable of undergoing oxidation-reduction reactions, glutathione, NAD and NADP, were determined in muscle tissues of young and old rats. A considerable increase in the relative concentration of the oxidized form, at the expense of the reduced one was found in the old tissue reflecting a significantly less reducing environment than in young cells. The effects of varying the ratio of reduced/oxidized glutathione in vitro on the activity of the enzyme glyceraldehyde-3-phosphate dehydrogenase extracted from young and old animals were compared. It was found that concentrations of GSSG as found in old muscle tissue do not affect enzyme samples extracted from young muscle. The accumulation of oxidized glutathione observed in old cells does not, therefore, directly cause the age-related activity loss of this enzyme.