磷脂在大鼠心肌线粒体上的超微结构定位方法

选用Wister成年大鼠心肌,对Dermer氏磷脂定位法加以改进。通过延长固定时间及将三合固定以外各步均在4℃进行,以增强对组织结构的保护作用,防止磷脂移位扩散。加以改进的方法,能清晰地显示富含磷脂的膜系结构,尤其是线粒体磷脂在嵴膜及内外膜的定位。此外,超薄切片均不经铅铀复染,以消除其它非磷脂成分的干扰。同时采用脱脂、去三合固定作双重阴性对照,证实了磷脂定位的特异性。     

不育男性精子线粒体DNA突变与线粒体超微结构改变

目的：探讨精子线粒体DNA突变和线粒体超微结构变化与男性不育之间的关系。方法：应用PCR技术,DNA测序技术对不育男性的76例精了动力差的精液标本进行MTCYB、MTATP6片段检测,从中选出5例有线粒体DNA缺失的标本进行透射电镜观察。结果5例病人的标本电镜下大多数精子尾部可见线粒体有体积异常,或为小线粒体,或为大线粒体,排列紊乱,,分布不对称;多层线粒体包绕尾部轴丝。与已育男性的精子标本的形态差别明显。结论：线粒体DNA突变的精子标本可以观察到线粒体结构改变。精子线粒体DNA的突变和线粒体结构的改变均可影响精子受精过程的能量供给,可导致男性不良。     

低氧预适应对移植大鼠肝细胞线粒体超微结构的影响

目的 观察低氧预适应(HP)对移植大鼠肝细胞线粒体超微结构的影响. 方法 采用改良的自体肝移植模型模拟肝移植过程,将72只SD大鼠随机分为正常对照(NC)、自体移植(AT)和低氧预适应(HP)3个组,每组24只.HP为术前用8%氮氧混合气体处理90min,分别于术后1、6、24h处死大鼠取肝脏标本,透射电镜观察肝细胞及线粒体的形态学改变,并用图像分析系统定量评判线粒体超微结构的改变程度. 结果 透射电镜下见AT组线粒体肿胀明显,膜模糊不清,部分膜破裂,线粒体嵴疏松溶解,有空泡形成;而HP组线粒体结构基本正常,仅有轻度肿胀,线粒体排列整齐,膜基本完整,线粒体嵴密集,未见空泡形成;定量分析线粒体的面积、周长及直径均和AT组有显著性差异(P<0.05),HP组线粒体损伤程度较AT组有明显改善. 结论 线粒体超微结构的改变是移植后肝细胞损伤的早期变化,HP可改善这一变化以减轻肝细胞损伤.     

卵巢癌VEGF表达及癌细胞线粒体超微结构的改变

目的:观察卵巢癌血管内皮生长因子(VEGF)表达及癌细胞线粒体超微结构的改变,探讨卵巢癌VEGF表达增强对线粒体的影响及其机制。方法:用免疫组化染色法及电子显微镜技术研究卵巢癌VEGF表达及癌细胞线粒体超微结构的改变及相互关系。结果:免疫组化结果显示,微血管内皮细胞及卵巢上皮细胞VEGF表达呈强阳性。癌变后的卵巢上皮细胞的线粒体数量增多,线粒体明显肿胀、脊断裂明显。结论:卵巢癌线粒体超微结构的改变与VEGF表达有关,其VEGF表达增强可能是癌细胞自我保护机制的反应。     

小鼠胚着床前线粒体的分布和超微结构变化

为了解小鼠着档前细胞中线粒体的分布和超微结构的变化规律，观察了２细胞胚，４细胞胚，８细胞胚，桑椹胚，早期囊胚和晚期囊胚，２细胞期和桑椹胚期，线粒体绕胞核集，在挤紧的８细胞胚中，线粒体在细胞接触面处的胞质边缘密集。囊胚期，滋养层细胞的线粒体在胞核周围较宽的区域中分布。     

局灶性脑缺血大鼠脑细胞超微结构及线粒体呼吸功能变化的研究

目的研究大鼠脑细胞超微结构及脑组织线粒体呼吸链功能在局灶性脑缺血前后的变化。方法采用改良Zea-Longa方法复制大鼠大脑中动脉缺血（middle cerebral anery occlusion MCAO）模型，透射电镜观察缺血后脑组织神经元超微结构的改变；检测线粒体NAD链及FAD链R3、R4、RCR、P／O等评价呼吸功能的指标。结果局灶性脑缺血大鼠脑组织神经元细胞结构严重破坏，线粒体NAD链和FAD链的R3（P〈0．01）、P／O（NAD链P〈0．01，FAD链P〈0．05）、RCR（P〈0．01）明显低于假手术组，R4明显高于假手术组（P〈0．05）。结论脑缺血后线粒体结构破坏，功能受损，通过保护线粒体呼吸链可能对脑缺血损伤有保护作用。     

植物雌激素对去卵巢大鼠海马神经元线粒体超微结构的保护作用

采用去卵巢(OVX)SD大鼠模拟女性绝经后神经元的退变来观察雌激素、植物雌激素对海马神经元线粒体的保护作用。雌性SD大鼠分为5组:(1)正常对照组;(2)去卵巢对照组;(3)雌激素治疗组;(4)金雀异黄酮治疗组;(5)依普拉芬治疗组,并于术后12d取材进行超微结构观察和体视学定量分析。结果显示:(1)去卵巢后海马神经元的线粒体肿胀明显,嵴断裂明显,空泡化显著;3个治疗组细胞和线粒体相对于去卵巢对照组均有明显改善;(2)与去卵巢对照组相比较,3个治疗组线粒体的体积密度(Vv)、平均直径(D)、平均表面积(S)明显减小(P<0.05);3个治疗组的比表面(δ)、数密度(Nv)和粒子分散度(Cλz)较去卵巢对照组明显增大(P<0.05)。以上结果表明:雌激素和植物雌激素对去卵巢后大鼠的海马神经元线粒体具有保护作用。本研究结果为雌激素和植物雌激素以线粒体为靶点防治女性更年期后神经元的退变及老年性痴呆可能的作用机制提供了一定的形态学资料。     

浆液性与黏液性卵巢囊腺癌线粒体超微结构及体视学

目的观察黏液性卵巢囊腺癌(MC)及浆液性卵巢囊腺癌(SC)细胞线粒体超微结构及体视学特点的改变,探讨两种腺癌线粒体体视学改变的临床意义及其可能机制。方法用电镜观察超微结构,并用体视学检测线粒体的体密度(Vvm)、外膜面密度(Sv,μm-1)、表面积体积比(Rsv,μm-1)及其相互关系。结果癌变后的卵巢囊腺癌细胞线粒体明显增多,线粒体肿胀、嵴断裂明显。MC细胞Vvm和Sv分别为0.07±0.06和0.06±0.04,显著低于正常的0.14±0.07和0.09±0.05(P<0.05),但线粒体Rsv则明显升高(0.89±0.04,P<0.05)。SC细胞线粒体Vvm和Sv明显升高,分别为0.27±0.12和0.12±0.06(P<0.01),而线粒体Rsv则明显降低(0.58±0.49,P<0.05)。结论 MC与SC的线粒体体视学改变不同,前者以减少为主,而后者则以增大为主。     

异丙基肾上腺素致大鼠心肌损伤的超微结构及体视学研究

实验用Ｗｉｓｔａｒ大鼠３５只，体重２１０ｇ。异丙肾（ＩＳＰ）组２８只，皮下注射ＩＳＰ５．０ｍｇ／ｋｇ，注射后４、１２、２４和４８小时分别处死７只大鼠，随同处死对照组７只。光镜观察心肌坏死部位和程度；电镜观察心肌超微结构变化；用体视学方法定量分析心肌线粒体形态变化。结果表明：心肌线粒体Ｖｖ和Ｖ值升高，与对照组比较差异显著（Ｐ＜０．０１），ＮＡ和Ｎｖ值变化与对照组比较无显著差异（Ｐ＞０．０５）。实验表明线粒体Ｖｖ和Ｖ植升高主要与线粒体肿胀有关，与线粒体的集聚和增生无关；线粒体的损伤破坏与心肌坏死程度密切相关；并提示注射ＩＳＰ后４８小时是制作大鼠心肌坏死模型的最佳时间。     

大鼠心肌线粒体细胞色素氧化酶琥珀酸脱氢酶的超微结构定位

一、琥珀酸脱氢酶(SDH)超微结构技术的改进:合理筛选固定时间及固定剂浓度;组织在基质中孵育后再经DAB处理,对不同时间孵育后的组织作动态性观察。二、细胞色素氧化酶(CCO):选择合适的固定剂种类,固定时间及固定剂浓度;筛选最适孵育时间;低温脱水。     

Effect of immobilization on myocardial mitochondrial energy metabolism and ultrastructure in rats of different zoosocial ranks

I. M. Sechenov First Moscow Medical Institute. P. K. Anokhin Institute of Normal Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR K. V. Sudakov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 9, pp. 318–321, September, 1990.     

Effect of the assisted circulation on myocardial ultrastructure

The effect of a method of assisted circulation (counterpulsation) on the ultrastructure of the myocardium was studied in dogs. Electron microscopy revealed a sharp increase in the glycogen content in the heart muscle cells, mitochondria with a highly osmophilic, finely granular matrix, and high pinocytotic activity of the capillary endothelial cells. The results are evidence of metabolic changes in the myocardium and, in particular, that the myocardial muscle cells are functioning at a lower energy level. The changes discovered in the myocardial ultrastructure evidently account for the beneficial therapeutic effect of the method.Institute of Transplantation of Organs and Tissues, Ministry of Health of the USSR. Department of Pathological Anatomy, Moscow Medical Stomatological Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR B. V. Petrovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 12, pp. 1497–1499, December, 1976.     

Effect of high sustained +Gz stress on myocardial mitochondrial ultrastructure, respiratory function, and antioxidant capacity in rats

Exposure to high sustained positive acceleration (+Gz) is known to have a pathophysiological effect on the heart of the rat. As critical regulators of cardiac myocyte survival and death, mitochondria may be crucially involved in +Gz-induced pathogenesis. It was, therefore, of interest to investigate myocardial mitochondrial ultrastructure, respiratory function, and antioxidant capacity in rats after exposure to +10 Gz for 5 min. The results showed that high +Gz stress could damage mitochondrial ultrastructure; this was apparent from swollen, degenerated, and reduced mitochondria, and mitochondrial cristae broken or disappeared. This resulted in significant changes of quantitative indicators of mitochondria morphometry, for example increased surface density, volume density, average volume, and average surface area, and reduced numerical density. The studies also revealed that exposure to +Gz stress induced dysfunction of the mitochondrial respiratory chain, reduced the activity of antioxidant enzymes (catalase, superoxide dismutase, and glutathione peroxidase), and increased malondialdehyde content. We thus conclude that high +Gz stress not only damaged mitochondrial ultrastructure but also impaired respiratory function and antioxidant capacity.     

The effect of verapamil cardioplegia on myocardial ultrastructure

The calcium channel blocker, verapamil, was evaluated as an adjunct to cold cardioplegia in 16 randomized patients with unstable angina pectoris who received saphenous vein bypass grafts. Myocardial biopsies taken before cardioplegia showed various degrees of ischemic change as assessed by ultrastructural parameters (mitochondrial swelling, matrix clearance, and sarcotubular dilatation). After reperfusion, the majority of the patients had progressive changes of ischemia, with marked mitochondrial and sarcotubular swelling, depletion of glycogen, chromatin clumping, and myofibrillar disruption; amorphous mitochondrial densities were occasionally seen. The ultrastructural changes after cardioplegia were dependent primarily on the extent of preexisting ischemic damage and did not correlate with the use of verapamil. Verapamil did not protect the ischemic myocardium during cold cardioplegia as assessed ultrastructurally.     

缺血后处理对离体大鼠心肌线粒体功能的影响

目的：建立离体大鼠心肌缺血/再灌注损伤模型,观察缺血后处理对大鼠心肌线粒体功能的影响,并探讨线粒体ATP敏感性钾通道（mitoK_ATP）在缺血后处理心肌保护中的作用。方法：采用Langendorff装置建立离体大鼠心肌缺血/再灌注损伤模型。将SD大鼠随机分为对照组（C）、模型组（M）、缺血后处理组（IPO）、5-羟癸酸拮抗缺血后处理组（5-HD+IPO）,每组8只。各组均先灌注平衡20 min,C组：续灌70 min;M组：缺血前灌注4 ℃ St.Thomas停跳液（10 mL/kg）,全心缺血40 min,复灌30 min;IPO组：全心缺血40 min,复灌前先开放10 s,缺血10 s,反复6次,时间为2 min,复灌28 min;5-HD+IPO组：缺血后处理前给予含5-羟癸酸（100 μmol/L）的K-H液灌注5 min,余同IPO组,复灌23 min。观察各组平衡末与再灌注末心肌线粒体膜电位、氧自由基及呼吸功能的变化。结果：(1) 各组再灌注末心肌线粒体膜电位较平衡末显著降低,而C组显著高于其它3组,IPO组明显高于5-HD+IPO与M组,5-HD +IPO组高于M组。(2) 各组再灌注末与平衡末比较,心肌线粒体氧自由基含量显著升高,其中M组显著高于其它3组,5-HD +IPO组高于IPO及C组,IPO组高于C组。(3) 各组再灌注末较平衡末线粒体呼吸功能明显受损,且C组优于其它3组,IPO组优于5-HD+IPO与M组,5-HD +IPO组优于M组。结论：(1) 缺血后处理通过维护线粒体膜电位稳定、减少线粒体氧自由基的产生、保护线粒体呼吸链及功能,减轻心肌的再灌注损伤。(2) 5-HD不能完全阻断缺血后处理的心肌保护作用。(3) 缺血后处理的心肌保护效应可通过激活心肌mitoK_ATP实现,同时还有其它因素参与了缺血后处理的心肌保护。     

缺血预处理对糖尿病大鼠缺血/再灌注损伤性心肌超微结构的影响

目的:研究缺血预处理对糖尿病大鼠缺血再灌注损伤性心肌超微结构的影响。方法:建立糖尿病大鼠、缺血再灌注和缺血预处理模型,随机分成6组,即非糖尿病和糖尿病的假手术组、缺血再灌注组、缺血预处理组,观察心肌酶和心肌超微结构变化。结果:非糖尿病的缺血预处理组心肌酶CK、CK-MB、LDH较缺血再灌注组明显降低,心肌超微结构损伤减轻;糖尿病缺血预处理组与缺血再灌注组相比心肌酶无降低,心肌超微结构损伤进一步加重。结论:缺血预处理对非糖尿病大鼠心肌具有保护作用,而对糖尿病大鼠心肌不具有同样的保护作用。     

Effect of cholera toxin on mitochondrial ultrastructure and function in the epitheliocytes of the rabbit small intestine

Ultrastructural changes in the mitochondria of the epitheliocytes of the rabbit small intestine under the influence of cholera toxin took the form of widening of the intracristal and intermembranous spaces, probably reflecting their transition from the mainly orthodox to the mainly condensed configuration. Similar changes were observed in isolated mitochondria in Chance's states 4 and 3 in a saline medium with 2% polyvinylpyrrolidone. The respiratory control coefficient of mitochondrial isolated from the tissue of pathologically changed organs was the same as the normal control. It is suggested that the ultrastructural changes found in the mitochondria through the action of cholera toxin are due to transition of the mitochondria from state 4 into state 3 in connection with an increase in the ADP concentration in the cell as a result of activation of ATPases.Laboratory of Cell Pathology and Electron Microscopy, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 8, pp. 229–233, August, 1979.