麝香保心丸对一次性力竭运动大鼠心肌损伤标记物和C反应蛋白的影响

目的探讨麝香保心丸对一次性力竭运动大鼠心肌损伤标记物和C反应蛋白的影响。方法选择雄性Wistar大鼠52只,随机分成实验组和对照组,每组26只。两组大鼠每天自由进食饮水相同,实验组大鼠每天麝香保心丸2粒(每粒22.5 mg)分2次灌胃,共两周。两组均接受力竭游泳运动,制成力竭运动动物模型,分别测定和比较两组大鼠血清和心肌组织肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、肌钙蛋白T(Tn T)、B型脑钠肽(BNP)和C反应蛋白(CRP)水平。结果大鼠平均力竭运动游泳时间实验组较对照组明显延长(P0.01)。实验组血清和心肌组织CK、CK-MB、Tn T、BNP和CRP水平均明显低于对照组(P0.05)。结论麝香保心丸可显著降低力竭运动大鼠血清和心肌中CK、CK-MB、Tn T、BNP和CRP水平,能够减轻力竭运动后心肌损伤。     

心肌坏死标志物联合检测对急性心肌梗死早期诊断及鉴别的价值

目的:探讨心肌坏死标志物联合检测在急性心肌梗死早期诊断及鉴别中的意义。方法:选取2010年12月至2013年5月我院收治的90例患者,45例确诊急性心肌梗死患者为观察组,其余45例非急性心肌梗死患者为对照组。分别采集两组患者静脉血4 m L用于检验。采用免疫抑制法测定患者血清中肌酸激酶(CK)和肌酸激酶同工酶(CK-MB)含量,采用电化学发光法检测肌钙蛋白I(c Tn I)和肌红蛋白(MYO)含量。观察并比较不同时间点两组患者血清中CK、CK-MB、c TnⅠ及MYO含量的变化情况。结果:与对照组比较,观察组的血清CK、CK-MB、c TnⅠ及MYO的含量明显升高,其中CK及MYO升高最为显著,差异具有统计学意义(P0.05)。CK、CK-MB在发病3~6 h后快速升高,24 h达高峰;c TnⅠ前24 h与CK-MB同步,但维持时间较长;MYO在发病后1~2 h发生异常,12 h达峰值(P0.05)。结论:心肌坏死标志物联合检测可提高急性心肌梗死的检出率,有助于疾病的及时发现、诊断和治疗。     

猪腹部火器伤肠管穿透后心肌损伤的变化

目的:观察腹部火器伤肠管穿透后心肌损伤的变化.方法:健康长白仔猪42头随机分为对照组以及伤后1h、2h、4h、8h、12h和24h组.实验组建立腹部火器伤肠管穿透模型后,分别测定伤后1 h、2h、4h、8h、12h和24h组各组动物血清中LDH、CK、CK-MB水平,并与对照组比较,观察实验组各时间点心脏组织学变化?结果:伤后各组血清LDH、CK、CK-MB水平均高于对照组.伤后8h、12h、24h组光镜下出现逐渐加重的心肌细胞水肿、变性;电镜下4h、8h、12h、24h组出现逐渐的线粒体肿胀、溶解;对照组光、电镜下未见明显的损伤性变化.结论:腹部火器伤肠管穿透导致心肌形态和酶的损伤性变化,随着伤后时间的延长而加重.     

牛磺酸对运动大鼠甲状腺激素及心肌第二信使的影响

目的：探讨牛磺酸对力竭运动后大鼠心肌损伤的保护作用。方法：以大鼠力竭运动为模型,研究牛磺酸对血清和心肌中四碘甲腺原氨酸（T4）和三碘甲腺原氨酸（T3）,心肌T45’－脱单碘酸（T45’－DI）活性、环磷酸腺苷（cAMP）水平的影响。结果：力竭运动可造成血清和心肌中T3水平、心肌中T45’－DI活力和cAMP含量显著升高（P＜0．01）,T4水平无显著性改变;而补充牛磺酸可显著抑制力竭运动后大鼠血清和心肌中T3水平的升高,抑制心肌中T45’－DI活力和cAMP含量的显著增加。结论：牛磺酸对大鼠力竭运动后心肌损伤具有一定的保护作用。     

预热处理对离心运动大鼠骨骼肌超微结构、血清CK、LDH及氧化应激的影响

目的：采用离心运动和热处理研究预热处理对离心运动大鼠骨骼肌的保护作用。方法：SD大鼠分安静组（n=8）,运动组（n=32）和预热处理运动组（n=40）,运动组运动完成后分为运动即刻组（E1）、运动后24 h组（E2）、运动后48 h组（E3）和运动后6 d（E4）组,热处理组在4个周期热处理后分热处理安静组（HE）、热处理运动即刻组（HE1）、热处理运动后24 h组（HE2）、热处理运动后48 h组（HE3）和热处理运动后6 d（HE4）组;运动采用-16°坡度、速度20 m/min、时间120 min的一次性离心力竭跑台运动至力竭模型;预热处理采用每4 d为一个周期,3 d进行热处理、1 d休息,共4个周期,期间湿度控制在50%,肛温起始温度从39 ±0.5℃,依次递增到39.5 ±0.5℃、40.5 ±0.5℃和41.5 ±0.5℃,监测大鼠直肠温度达到预定值以后维持15 min。实验后取血和骨骼肌,观察骨骼肌超微结构和血清肌酸激酶（CK）、乳酸脱氢酶（LDH）及氧化应激指标的变化。结果：预热处理运动后不同时相血清CK、LDH值低于单纯运动组,其中HE1及HE2组与同时相的E1、E2的CK值都呈显著性差异（P < 0.05）,HE1、HE2及HE3组的血清LDH值显著低于同时相的E1、E2及E3组（P < 0.05）;HE2及HE3组的血清超氧化物歧化酶（SOD）值都分别高于同时相的E1、E2组,并且两两之间呈显著性差异（P < 0.05）,HE2组的血清丙二醛（MDA）值显著低于E2组（P < 0.05）。结论：运动预热处理对预防运动性骨骼肌损伤有一定作用。     

美洲大蠊提取物对力竭运动大鼠心血管氧化损伤的保护作用

目的:通过美洲大蠊提取物(PAE)对力竭运动大鼠心肌自由基代谢的影响,探讨其对心肌氧化损伤的保护作用。方法:雄性SPF级健康SD大鼠40只,随机分为安静组、运动组、美洲大蠊提取物安静组、美洲大蠊提取物运动组(n=10)。服药组每天灌服2 ml美洲大蠊提取物(美洲大蠊提取物按50 mg/kg配制,溶于2 ml蒸馏水中灌胃给药),对照组每次灌蒸馏水2 ml。每天灌胃1次,连续灌胃14 d后,美洲大蠊提取物运动组与运动组大鼠进行一次性力竭游泳运动建立力竭模型,记录大鼠力竭运动时间。力竭运动结束时即刻取样,检测血清中丙二醛(MDA)含量、谷胱甘肽过氧化物酶(GSH-Px)和超氧化物歧化酶(SOD)活性,并检测观察心肌组织中一氧化氮合酶(NOS)基因的表达情况。结果:与安静组相比,一次力竭游泳后,运动组心肌SOD、GSH-Px的活性明显降低(P0.01),而MDA含量显著升高(P0.01);而美洲大蠊提取物能够显著提高力竭SD大鼠的心肌SOD、GSH-Px的活性(P0.01),降低MDA含量(P0.01),e Nos基因表达增高。结论:大鼠力竭运动后心肌会发生氧化损伤,美洲大蠊提取物干预后能够增加力竭运动后大鼠心肌的抗氧化能力,对力竭运动所致心肌损伤具有一定的保护作用,进而增强大鼠运动能力。     

大蒜素对运动大鼠心肌脂质过氧化反应的干预作用研究

研究大蒜素对大鼠大负荷运动后心肌脂质过氧化反应的干预作用及机制。将成年雄性SD大鼠48只,随机分为安慰剂组(A组)和用药组(B组),B组每日定时经口腔灌胃给予大蒜素30 mg/kg体重,A组给予相同体重比例的安慰剂(蒸馏水)。两周后观察各组在安静时及完成一次性大负荷游泳运动后即刻、运动后24 h心肌超微结构变化,并测定心肌组织SOD、MDA、TAC和血清CK-MB等指标。结果显示运动后两组大鼠心肌超微结构都出现改变和损伤,B组表现较轻微。B组在运动后两个时相心肌SOD和TAC均显著高于A组;心肌MDA和血清CK-MB非常显著低于A组。提示大蒜素有助于减轻大负荷运动导致的心肌脂质过氧化反应。     

急性力竭运动后小鼠肾细胞凋亡水平的变化及牛磺酸的保护作用

为探讨急性力竭运动后小鼠(Mus musculus)肾细胞凋亡水平的时相性变化及牛磺酸对肾的保护作用,将56只雄性小鼠随机分为对照组、力竭运动组(分为运动后即刻组、12h组、24 h组和48 h组)及牛磺酸运动组(分为12h组和24 h组),每小组8只,一次性力竭游泳运动后检测肾细胞凋亡水平、Bcl-2和Bax蛋白表达、一氧化氮(NO)含量及结构型一氧化氮合酶(cNOS)、诱导型一氧化氮合酶(iNOS)活性的变化.结果显示,力竭运动后各组小鼠肾细胞凋亡水平呈先升高后下降的趋势,其中运动后24 h组的凋亡水平达峰值(P＜0.05).与对照组相比,运动各组Bax表达均显著增强(P＜0.05).除运动后即刻组外,运动各组Bcl-2表达显著减弱(P＜0.05).各组Bax/Bcl-2比值显著升高,并在运动后24 h达峰值(P＜0.01),后出现下降趋势.小鼠力竭游泳后24 h和48 h肾组织NO含量显著高于对照组(P＜0.05),同时iNOS活性升高(P＜0.01),cNOS活性无显著性变化.相比同时刻运动组,牛磺酸运动组小鼠肾细胞凋亡水平、Bax表达及Bax/Bcl-2比值、iNOS活性显著降低(P＜0.05),Bcl-2表达显著升高(P＜0.05).以上结果表明,急性力竭运动可导致肾细胞凋亡的发生,iNOS、Bax、Bcl-2水平及Bax/Bcl-2比值可能在肾细胞凋亡的发生过程中发挥重要的介导作用.牛磺酸可通过调控iNOS活性及Bax/Bcl-2比值,抑制急性力竭运动后小鼠肾细胞凋亡的发生.     

高原移居战士运动后心肌酶和心功能的变化及红益胶囊的干预作用

目的：探讨高原移居战士运动后心肌酶和心功能的变化及红益胶囊的干预作用。方法：平原入伍到高原6个月~24个月的健康男性战士8名,分别在服用红益胶囊前及服药5 d、8 d,检测运动前静息状态、运动后即刻的心肌作功指数（Tei指数）、左心室射血分数（LVEF）及30 min时的血清肌酸激酶同功酶-MB（CK-MB）和心肌肌钙蛋白I （cTnI）。结果：在静息状态下,服药前、服药5 d、8 d运动后Tei指数、血清C K-MB、cTnI水平均明显增高,LVEF均明显降低（P<0.01）;与服药前运动后比较,服药8 d,运动后Tei指数、血清CK-MB、cTnI水平均明显降低、LVEF明显升高（P<0.01）。结论：平原移居高原久居战士在高原中等强度负荷运动时,有明显的心肌损伤及心功能降低。红益胶囊对减轻人体在高原体力负荷劳动时心肌缺氧性损伤,增强心功能有明显作用。     

杜仲多糖改善运动疲劳的研究

目的：评价杜仲多糖（EUP）抗运动性疲劳的效果。方法：40只昆明小鼠建立一个5周的小鼠游泳模型,将小鼠分为运动对照组、蔗糖对照组、高剂量EUP组和低剂量EUP组（n=10）,服药采取灌胃的方式。训练期结束后,测定各组小鼠的体重变化与游泳力竭时间、力竭游泳后动物的血糖浓度、血乳酸（BLA）浓度、血尿素氮（BUN）浓度、肌酸激酶（CK）活性、肝糖原、肌糖原含量变化。结果：EUP高剂量与低剂量组小鼠较对照组体重增加明显,E UP高剂量游泳力竭时间显著延长（P<0.05）、血清CK活性和BUN含量显著下降（P <0.05）,但血糖、肝肌糖原以及BLA的水平变化不明显。结论：EUP具有抗运动性疲劳的作用,其机理与其调节机体糖代谢、节约蛋白质有关。     

The effect of a carbohydrate and protein supplement on resistance exercise performance, hormonal response, and muscle damage

The purpose of this study was to determine whether resistance exercise performance and postexercise muscle damage were altered when consuming a carbohydrate and protein beverage (CHO-PRO; 6.2% and 1.5% concentrations). Thirty-four male subjects (age: 21.5 +/- 1.7 years; height: 177.3 +/- 1.1 cm; weight: 77.2 +/- 2.2 kg) completed 3 sets of 8 repetitions at their 8 repetition maximum to volitional fatigue. The exercise order consisted of the high pull, leg curl, standing overhead press, leg extension, lat pull-down, leg press, and bench press. In a double-blind, posttest-only control group design, subjects consumed 355 ml of either CHO-PRO or placebo (electrolyte and artificial sweetener beverage) 30 minutes prior to exercise, 177 ml immediately prior to exercise, 177 ml halfway through the exercise bout, and 355 ml immediately following the exercise bout. There were no significant differences between groups relative to exercise performance. Cortisol was significantly elevated in the placebo group compared to the CHO-PRO group at 24 hours postexercise. Insulin was significantly elevated immediately pre-exercise, after the fourth lift, immediately postexercise, 1 hour, and 6 hours postexercise in CHO-PRO compared to the placebo group. Myoglobin levels in the placebo group approached significance halfway through the exercise bout and at 1 hour postexercise (p = 0.06 and 0.07, respectively) and were significantly elevated at 6 hours postexercise compared to the CHO-PRO group. Creatine kinase levels were significantly elevated in the placebo group at 24 hours postexercise compared to the CHO-PRO group. The CHO-PRO supplement did not improve performance during a resistance exercise bout, but appeared to reduce muscle damage, as evidenced by the responses of both myoglobin and creatine kinase. These results suggest the use of a CHO-PRO supplement during resistance training to reduce muscle damage and soreness.     

Calpain-3 is autolyzed and hence activated in human skeletal muscle 24 h following a single bout of eccentric exercise.

The function and normal regulation of calpain-3, a muscle-specific Ca(2+)-dependent protease, is uncertain, although its absence leads to limb-girdle muscular dystrophy type 2A. This study examined the effect of eccentric exercise on calpain-3 autolytic activation, because such exercise is known to damage sarcomeric structures and to trigger adaptive changes that help prevent such damage on subsequent exercise. Six healthy human subjects performed a 30-min bout of one-legged, eccentric, knee extensor exercise. Torque measurements, vastus lateralis muscle biopsies, and venous blood samples were taken before and up to 7 days following the exercise. Peak isometric muscle torque was depressed immediately and at 3 h postexercise and recovered by 24 h, and serum creatine kinase concentration peaked at 24 h postexercise. The amount of autolyzed calpain-3 was unchanged immediately and 3 h after exercise, but increased markedly (from approximately 16% to approximately 35% of total) 24 h after the exercise, and returned to preexercise levels within 7 days. In contrast, the eccentric exercise produced little autolytic activation of the ubiquitous Ca(2+)-activated protease, mu-calpain. Eccentric exercise is the first physiological circumstance shown to result in calpain-3 activation in vivo.     

Time course of endothelial adaptation after acute and chronic exercise in patients with metabolic syndrome

Clustering of cardiovascular risk factors may lead to endothelial dysfunction. Physical exercise is an important factor in prevention and treatment of endothelial dysfunction. We wanted to determine the time course of adaptation to a single bout of exercise at either high or moderate intensity upon endothelial function both before and after a 16-week fitness program in patients with metabolic syndrome. Twenty-eight patients with metabolic syndrome participated in the study and were randomized and stratified (according to age and sex) into an aerobic interval exercise training group (AIT, n = 11), a continuously moderate-intensity exercise training group (CME, n = 8) or to a control group (n = 9). Flow-mediated dilatation (FMD) was determined at baseline, immediately, 24, 48, and 72 hours after 1 bout of exercise and repeated after 16 weeks of exercise. In the untrained state, FMD improved from 5 to 11% (p = 0.003) immediately after a single bout of aerobic interval training (AIT), an effect lasting 72 hours postexercise. In comparison, continuous moderate exercise (CME) improved FMD immediately after a single bout of exercise from 5 to 8% (p = 0.02), an effect lasting 24 hours postexercise (group difference, p < 0.001). In the trained state, a single bout of AIT resulted in a 2% (p = 0.007) acute increase of FMD lasting 48 hours postexercise. The CME increased FMD by 3% (p < 0.01), an effect lasting 24 hours postexercise (group difference p = 0.0012). Blood glucose level decreased after 1 single bout of AIT in the untrained state (p < 0.05), and the effect lasted at least 72 hours postexercise (p < 0.01). Acute CME decreased blood glucose with normalization of the values 24 hours postexercise (p < 0.01). A single bout of exercise in the trained state reduced fasting blood glucose by 10% (p < 0.05) after both AIT and CME. Exercise training, especially high intensity, thus appears to be highly beneficial in reducing blood glucose and improving endothelial function.     

血清CREG蛋白在急性心肌梗死早期的表达研究

目的：探讨血清中CREG蛋白在急性心肌梗死发作早期的表达情况,尝试为临床心肌缺血的极早期诊断提供一种新的血清标志分子。方法：在2010年6月至2010年11月期间,入选在沈阳军区总医院心内科住院治疗的急性ST段抬高型心肌梗死患者50例及非AMI对照50例,于AMI组胸痛发作后的不同时间点采血测定CK、CK—MB、LDH和cTnT,同时应用Westem blot技术测定血清中CREG蛋白的含量,并与对照组比较。结果：AMI组发病72小时内的血清中CREG蛋白表达均较对照组有不同程度的增高（P〈0．05）。胸痛开始2h内,AMI组血清中CREG的含量即明显增高,其在2h、4h及6h的含量显著高于对照组（P〈0．001）。在胸痛已经发作2小时内,两组间血清cTnT、CK、CK-MB及LDH水平比较无统计学意义（P〉0．05）。结论：CREG在AMI患者血清中的表达增高．其在血清中表达时间早于cTNT及CK-MB。     

Cellular adaptation to repeated eccentric exercise-induced muscle damage.

Eccentrically biased exercise results in skeletal muscle damage and stimulates adaptations in muscle, whereby indexes of damage are attenuated when the exercise is repeated. We hypothesized that changes in ultrastructural damage, inflammatory cell infiltration, and markers of proteolysis in skeletal muscle would come about as a result of repeated eccentric exercise and that gender may affect this adaptive response. Untrained male (n = 8) and female (n = 8) subjects performed two bouts (bout 1 and bout 2), separated by 5.5 wk, of 36 repetitions of unilateral, eccentric leg press and 100 repetitions of unilateral, eccentric knee extension exercises (at 120% of their concentric single repetition maximum), the subjects' contralateral nonexercised leg served as a control (rest). Biopsies were taken from the vastus lateralis from each leg 24 h postexercise. After bout 2, the postexercise force deficit and the rise in serum creatine kinase (CK) activity were attenuated. Women had lower serum CK activity compared with men at all times (P < 0.05), but there were no gender differences in the relative magnitude of the force deficit. Muscle Z-disk streaming, quantified by using light microscopy, was elevated vs. rest only after bout 1 (P < 0.05), with no gender difference. Muscle neutrophil counts were significantly greater in women 24 h after bout 2 vs. rest and bout 1 (P < 0.05) but were unchanged in men. Muscle macrophages were elevated in men and women after bout 1 and bout 2 (P < 0.05). Muscle protein content of the regulatory calpain subunit remained unchanged whereas ubiquitin-conjugated protein content was increased after both bouts (P < 0.05), with a greater increase after bout 2. We conclude that adaptations to eccentric exercise are associated with attenuated serum CK activity and, potentially, an increase in the activity of the ubiquitin proteosome proteolytic pathway.     

MR measurements of muscle damage and adaptation after eccentric exercise.

The purposes of this study were, first, to clarify the long-term pattern of T2 relaxation times and muscle volume changes in human skeletal muscle after intense eccentric exercise and, second, to determine whether the T2 response exhibits an adaptation to repeated bouts. Six young adult men performed two bouts of eccentric biceps curls (5 sets of 10 at 110% of the 1-repetition concentric maximum) separated by 8 wk. Blood samples, soreness ratings, and T2-weighted axial fast spin-echo magnetic resonance images of the upper arm were obtained immediately before and after each bout; at 1, 2, 4, 7, 14, 21, and 56 days after bout 1; and at 2, 4, 7 and 14 days after bout 2. Resting muscle T2 [27.6 +/- 0.2 (SE) ms] increased immediately postexercise by 8 +/- 1 ms after both bouts. T2 peaked 7 days after bout 1 at 47 +/- 4 ms and remained elevated by 2.5 ms at 56 days. T2 peaked lower (37 +/- 4 ms) and earlier (2-4 days) after bout 2, suggesting an adaptation of the T2 response. Peak serum creatine kinase values, pain ratings, and flexor muscle swelling were also significantly lower after the second bout (P < 0.05). Total volume of the imaged arm region increased transiently after bout 1 but returned to preexercise values within 2 wk. The exercised flexor compartment swelled by over 40%, but after 2 wk it reverted to a volume 10% smaller than that before exercise and maintained this volume loss through 8 wk, consistent with partial or total destruction of a small subpopulation of muscle fibers.     

Delayed onset muscle soreness following repeated bouts of downhill running

Perceived muscle soreness ratings, serum creatine kinase (CK) activity, and myoglobin levels were assessed in three groups of subjects following two 30-min exercise bouts of downhill running (-10 degrees slope). The two bouts were separated by 3, 6, and 9 wk for groups 1, 2, and 3, respectively. Criterion measures were obtained pre- and 6, 18, and 42 h postexercise. On bout 1 the three groups reported maximal soreness at 42 h postexercise. Also, relative increases in CK for groups 1, 2, and 3 were 340, 272, and 286%, respectively. Corresponding values for myoglobin were 432, 749, and 407%. When the same exercise was repeated, significantly less soreness was reported and smaller increases in CK and myoglobin were found for groups 1 and 2. For example, the percent CK increases on bout 2 for groups 1 and 2 were 63 and 62, respectively. Group 3 demonstrated no significant difference in soreness ratings, CK activities, or myoglobin levels between bouts 1 and 2. It was concluded that performance of a single exercise bout had a prophylactic effect on the generation of muscle soreness and serum protein responses that lasts up to 6 wk.     

Effect of vitamin E and eccentric exercise on selected biomarkers of oxidative stress in young and elderly men

Muscle damage resulting from eccentric exercise provides a useful model of oxyradical-induced injury and can be used to examine age-related responses to oxidative stress. Sixteen young (26.4 ± 3.3 years) and 16 older (71.1 ± 4.0 years) healthy men were randomly assigned to 1000 IU/d vitamin E or placebo for 12 weeks and ran downhill for 45 min at 75% VO₂max, once before and following supplementation. Blood samples were obtained before (baseline) and immediately postexercise (0 h), and at 6, 24, and 72 h postexercise to determine antioxidant status, muscle damage, lipid peroxidation, and DNA damage. Following exercise, young and older men experienced similar increases in serum creatine kinase (CK), F₂-isoprostanes (iPF₂; p < .001) and malondialdehyde (MDA; p < .01), although iPF₂ peaked at 72 h postexercise and MDA peaked at 0 h. Oxygen Radical Absorbance Capacity (ORAC) decreased at 72 h (p < .01) and correlated with the rise in iPF₂, MDA, and CK in the young men (p < .05). Leukocyte 8-hydroxy-2′-deoxyguanosine (8-OHdG) was unaffected by exercise. Vitamin E decreased peak CK in young men, while in older men it decreased resting levels of iPF₂ and suppressed the 24 h postexercise increases in iPF₂ (p < .05). Thus, vitamin E supplementation induced modest changes eccentric exercise-induced oxidative stress, although differentially between the young and older subjects, while age had no direct influence on these responses among this group of physically fit subjects.     

短期和长期运动预适应对力竭大鼠心肌损伤的保护作用

目的：研究短期和长期运动预适应对心肌细胞凋亡保护中发挥的作用及机制。方法：48只雄性SD大鼠随机分为对照组（C）、力竭组（E）、短期运动预适应组（S-EP）、长期运动预适应组（L-EP）。短期和长期运动预适应分别进行3 d和3周的反复间歇游泳训练方案。光镜下观察心肌细胞的结构改变;ELISA方法检测血清中缺血修饰白蛋白（IMA）、磷酸肌酸同工酶（CK-MB）含量;实时荧光定量PCR和Western blot方法检测心肌组织中TNF-α、Caspase-8、Caspase-3基因和蛋白表达;采用DNA原位末端标记（TUNEL）法观察心肌细胞的凋亡情况。结果：与C组相比,E组心肌细胞损伤严重,血清IMA、CK-MB含量及心肌组织中TNF-α、Caspase-8、Caspase-3 mRNA和蛋白表达升高（P<0.05）;与E组相比,S-EP组血清CK-MB及心肌TNF-α、Caspase-8mRNA明显降低（P<0.05）,而蛋白表达无统计学差异,血清IMA及Caspase-3 mRNA和蛋白均下降不明显,无统计学意义（P>0.05）,L-EP组血清IMA、CK-MB含量及心肌TNF-α、Caspase-8、Caspase-3 mRNA及蛋白明显降低,有统计学意义（P<0.05）;与S-EP组相比,L-EP组血清IMA、CK-MB含量及TNF-α、Caspase-8、Caspase-3 mRNA和蛋白明显下降,有统计学意义（P<0.05）。E组心肌细胞凋亡明显,S-EP组和L-EP组均能抑制凋亡,且L-EP组与S-EP组相比心肌凋亡明显减少。结论：短期和长期运动预适应均可减轻力竭后的心肌损伤,但短期运动预适应并未改变Caspase蛋白酶的表达,长期运动预适应明显抑制Caspase-8、3 mRNA表达,减少蛋白合成,从而发挥心肌保护效应,故长期运动预适应在抑制心肌细胞凋亡方面较短期运动预适应更强。     

Exercise increases serum Hsp72 in humans

Recent evidence suggests that heat shock proteins (Hsps) may have an important systemic role as a signal to activate the immune system. Since acute exercise is known to induce Hsp72 (the inducible form of the 70-kDa family of Hsp) in a variety of tissues including contracting skeletal muscle, we hypothesized that such exercise would result in the release of Hsp72 from stressed cells into the blood. Six humans (5 males, 1 female) ran on a treadmill for 60 minutes at a workload corresponding to 70% of their peak oxygen consumption. Blood was sampled from a forearm vein at rest (R), 30 minutes during exercise, immediately postexercise (60 minutes), and 2, 8, and 24 hours after exercise. These samples were analyzed for serum Hsp72 protein. In addition, plasma creatine kinase (CK) was measured at these time points as a crude marker of muscle damage. With the exception of the sample collected at 30 minutes, muscle biopsies (n = 5 males) were also obtained from the vastus lateralis at the time of blood sampling and analyzed for Hsp72 gene and protein expression. Serum Hsp72 protein increased from rest, both during and after exercise (0.13 0.10 vs 0.87+/-0.24 and 1.02+/-0.41 ng/mL at rest, 30 and 60 minutes, respectively, P < 0.05, mean SE). In addition, plasma CK was elevated (P < 0.05) 8 hours postexercise. Skeletal muscle Hsp72 mRNA expression increased 6.5-fold (P < 0.05) from rest 2 hours postexercise, and although there was a tendency for Hsp72 protein expression to be elevated 2 and 8 hours following exercise compared with rest, results were not statistically significant. The increase in serum Hsp72 preceded any increase in Hsp72 gene or protein expression in contracting muscle, suggesting that Hsp72 was released from other tissues or organs. This study is the first to demonstrate that acute exercise can increase Hsp72 in the peripheral circulation, suggesting that during stress these proteins may indeed have a systemic role.