“标本配穴”电针对慢性心肌缺血模型大鼠线粒体结构及呼吸酶活性的影响

目的:以心肌线粒体为切入,观察“标本配穴”电针对慢性心肌缺血模型大鼠心肌线粒体结构、GAPDH、CS、CCO的酶活性及心肌组织ATP含量的影响,探讨“标本配穴”电针对慢性心肌缺血模型大鼠心肌线粒体的保护机制。方法:将30只Wistar雄性大鼠随机分为空白组、模型组、标本配穴组,每组10只。模型组、标本配穴组大鼠皮下注射盐酸异丙肾上腺素制备慢性心肌缺血大鼠模型。标本配穴组在造模结束后取“内关”“足三里”“关元”电针干预10 min,疏密波,2~100 Hz,1 mA,连续21天。运用透射电镜观察心肌线粒体结构变化,采用试剂盒检测3-磷酸甘油醛脱氢酶(GAPDH)、柠檬酸合成酶(CS)、细胞色素C氧化酶(CCO)的酶活性及心肌组织ATP含量。结果:与空白组比较,模型组线粒体结构破坏明显,大部分线粒体出现变形空泡化;而与模型组比较,标本配穴组线粒体结构损伤程度明显减轻。与空白组相比,模型组、标本配穴组心肌组织ATP含量、GAPDH、CS、CCO活性均明显降低(P<0.01)。但与模型组相比,标本配穴组4指标均显著增高(P<0.01),且心肌组织ATP含量与GAPDH、CS、CCO活性成线性相关。结论:在慢性心肌缺血状态下,标本配穴电针可提升线粒体呼吸酶活性,增加有氧呼吸产能效率,改善心脏能量代谢,从而减轻心肌细胞的结构破坏,对心肌组织起到保护作用。     

钼对缺硒大鼠心肌线粒体功能的影响

本文以克山病病区粮喂养大白鼠造成缺硒动物模型，以病区粮加钼作为处理因素，对大鼠心肌线粒体ＳＤＨ，ＣＣＯ活力及氧化磷酸化效率（Ｐ／Ｏ比值）做了测定。结果显示，钼对上述测定指标均有不同程度的改善，大剂量钼（４０ｍｇ／ｋｇ饲料）的作用优于小剂量钼（２．０ｍｇ／ｋｇ饲料），且与对照组相比有显著的统计学意义。此外，小剂量钼也能明显提高心肌线粒体ＳＤＨ活力。实验结果提示，改善心肌线粒体呼吸链功能及氧化磷酸化效     

高脂饲料对冷暴露大鼠细胞色素C氧化酶及脂蛋白脂酶活性和耐寒力的影响

大鼠预饲高脂饲料（占日摄入热量的２０％、３５％和４５％）１月后，进行急性（－１５℃，２ｈ和慢性（０℃，３ｗｋ）冷暴露。测定心肌线粒体细胞色素Ｃ氧化酶（ＣＣＯ）及肝线粒体脂蛋白脂酶（ＬＰＬ）活性及耐寒力。结果如下：（１）急性冷暴露组ＣＣＯ及ＬＰＬ活性明显高于慢性冷暴露组及室温对照组（Ｐ＜０．０１）。慢性冷暴露组的ＬＰＬ活性亦高于室温对照组。（２）０℃、８ｈ冷暴露时直肠温度下降幅度明显小于食用普通低脂饲料的大鼠（Ｐ＜０．０１）。（３）２０％和３５％脂肪组在０℃、３ｗｋ慢性冷暴露过程中，体重的恢复早于４５％脂肪组。结果提示预饲１个月高脂饲料，有利于提高耐寒力和加速冷适应，脂肪产热比以２０％～３０％为宜。     

Increase of cytochrome c oxidase negative fibers in rimmed vacuole myopathy with inflammatory changes

The physiological significance of cytochrome c oxidase (CCO) deficiency in rimmed vacuole myopathy (RVM) is not fully understood. Frequencies of CCO negative muscle fibers (CCO(?)F) were compared with two cases of in-clusion body myositis (IBM) and another two cases with RVM without inflammatory changes (i.e. oculopharyngeal distal myopathy (OPDM) and distal myopathy with rimmed vacuole formation (DMRV)). The frequencies of CCO(?)F were 6.9% in the case of definite IBM with 10 years of disease duration, 0.3% in possible IBM of 1 year duration, 1.3% in OPDM of 11 years duration, and 0.1% in DMRV of 2 years duration. The frequencies of CCO(?)F were generally higher in RVM than in controls. However, the incidence of CCO(?)F increased with time in patients with IBM compared with patients with RVM without inflammation. The present findings may provide important information on the myopathological distinction of IBM and RVM without inflammation.     

Cytochrome c oxidase activity is deficient in blood vessels of patients with myoclonus epilepsy with ragged-red fibers

Summary More than half of the intramuscular blood vessels in muscle biopsies from five patients with myoclonus epilepsy with ragged-fibers (MERRF) who had a point mutation in mitochondrial DNA at the tRNA^Lys region were darkly stained with succinate dehydrogenase (SDH) stain, showing the morphologic characteristics of strongly SDH-reactive blood vessels (SSV), but they had no cytochrome c oxidase (CCO) activity. By electron cytochemistry, the mitochondria in the smooth muscle cells of SSV had no CCO activity. On the other hand, SSV in muscle biopsies from patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) had normal CCO activity as shown by light and electron microscopy. The defect in CCO activity in the arteriolar smooth muscle cells and in muscle fibers suggests that CCO deficiency is related to the pathophysiology of MERRF.     

维生素B1对克山病病区粮所致心肌损伤的预防作用

把维生素 B_1加入克山病病区粮中喂饲大鼠两个月左右,可明显改善大鼠的营养状态;心肌细胞色素 C 氧化酶活性明显升高;使亚硝酸钠所致大鼠死亡率及心肌坏死面积明显降低。而对全血及心肌内的谷胱甘肽过氧化物酶活性,血清 T_3、T_4和皮质酮含量没有影响。提示我们除硒等因素缺乏外,维生素 B_1相对不足可能参与了克山病的发病。     

低水平激光治疗促进正畸牙齿移动的研究进展

低水平激光治疗（low-level laser therapy ,LLLT）是被FDA批准应用于临床的一种安全、无创的治疗方法,可通过使用600-1000nm的单色可见红光或近红外光对细胞和组织产生光生物刺激作用。目前,LLLT广泛应用于促进伤口愈合,缓解疼痛,减少炎症,再生医学等领域。现有研究认为,LLLT的分子和细胞机制主要与线粒体电子呼吸链有关,通过促进ATP的生成,调节细胞新陈代谢。大量研究表明,LLLT可通过促进牙周膜和牙槽骨的生理性改建,加速牙齿移动,进而缩短正畸治疗时间。由于LLLT的光生物刺激作用、非侵入性方式等特点使其在加速正畸牙齿移动方面有广泛的应用前景。本文就LLLT的作用机制,生物学效应及对正畸治疗中牙齿移动的促进作用进行探讨。     

Effect of aerobic training on 99mTc-methoxy isobutyl isonitrile (99mTc-sestamibi) uptake by myocardium and skeletal muscle: implication for noninvasive assessment of muscle metabolic profile

Aim: The effect of long‐term endurance training on skeletal muscle and myocardial uptake of ^99mTc‐sestamibi, a radiopharmaceutical accumulating in the mitochondria, was investigated. Methods: Twenty‐six Wistar rats were divided into a trained (5 days week^?1 endurance running for 14 weeks) and an untrained group. On completion of training, ^99mTc‐sestamibi was administered and, 2 h post‐injection, the myocardium and the soleus, extensor digitorum longus (EDL) and medial gastrocnemius (MG) muscles were removed for the measurement of cytochrome c oxidase (CCO) activity and ^99mTc‐sestamibi uptake. Tissue ^99mTc‐sestamibi kinetics was preliminarily studied in 16 other rats for up to 2 h post‐injection. Results: Two hours post‐injection ^99mTc‐sestamibi uptake was either stable (myocardium) or still rising (skeletal muscles). Both CCO activity and ^99mTc‐sestamibi uptake decreased in the same order (myocardium, soleus, EDL, MG) in the tissues examined. The CCO activity of the EDL and MG muscles was higher (P < 0.05) in the trained compared to the untrained group. ^99mTc‐sestamibi uptake in the soleus and EDL muscles was higher (P < 0.05) in the trained compared to the untrained rats, whereas the difference in MG was marginally significant (P = 0.06) in favour of the trained group. Conclusions: Long‐term endurance training, resulting in elevated skeletal muscle CCO activity, is also associated with a similar increase in ^99mTc‐sestamibi uptake. This finding suggests that ^99mTc‐sestamibi could be used in imaging assessment of skeletal muscle metabolism with possible applications in both clinical and sports medicine settings.