烧伤后大鼠肌组织唾液酸含量的变化

利用大鼠３０％Ⅲ度烧伤模型，探讨了烧伤大鼠心肌组织唾液酸含量的变化。同时还观察了心肌组织三磷酸腺苷酶活性和Ｃａ＾２＋含量改变。结果表明：烧伤后大鼠心肌组织唾液酸显著降低，伤后３小时仅为对照组的５８．８％，同时心肌组织Ｎａ＾＋，Ｋ＾＋－ＡＴＰａｓｅ，Ｍｇ＾２＋－ＡＴＰａｓｅ和Ｃａ＾２＋－ＡＴＰａｓｅ活性降低，而Ｃａ＾２＋含量明显升高。     

大鼠烧伤后心肌局部肾素-血管紧张素系统的改变

目的观察烧伤早期心肌局部肾素血管紧张素系统（ＲＡＳ）变化及其对心肌肌浆网（ＳＲ）钙运转功能的影响,探讨烧伤早期心功能障碍的发病机制。方法大鼠随机分为对照组（８只,不予致伤）,烧伤组（４０只,致３０％Ⅲ度烧伤）,治疗组（４０只,Ｌｉｓｉｎｏｐｒｉｌ灌胃３天后致３０％Ⅲ度烧伤）,测定烧伤前（对照组）及烧伤后３,８,２４ｈ左心功能变化,心肌组织血管紧张素转换酶（ＡＣＥ）活性,血管紧张素Ⅱ（ＡⅡ）及钙离子（Ｃａ２＋）含量变化,测定心肌ＳＲＣａ２＋ＡＴＰａｓｅ活性,及ＳＲＣａ２＋运转功能的变化。结果烧伤组大鼠左心室内压变化最大速率（±ｄｐ／ｄｔｍａｘ）明显降低,心肌组织ＡＣＥ活性、ＡⅡ及Ｃａ２＋含量显著增加,心肌ＳＲＣａ２＋ＡＴＰａｓｅ活性降低,ＳＲＣａ２＋摄取减少。治疗组预防性给予ＡＣＥ抑制剂Ｌｉｓｉｎｏｐｒｉｌ可显著降低烧伤后心肌组织ＡＣＥ活性,减少ＡⅡ产生,Ｃａ２＋含量降低,增加ＳＲＣａ２＋ＡＴＰａｓｅ活性,ＳＲＣａ２＋摄取增加,左心室功能明显改善。结论烧伤早期心肌局部ＲＡＳ迅速激活,抑制ＳＲＣａ２＋运转,可能是心肌ＲＡＳ促进烧伤早期心功能障碍的作用机制之一。     

地氟醚对大鼠心肌细胞质膜钙ATP酶活性的影响

目的 观察地氟醚对心肌细胞质膜Ｃａ＾２＋－ＡＴＰａｓｅ活性的影响，探讨其心肌抑制作用的机制。方法 参照文献方法制备大鼠心肌细胞质膜，观察不同浓度（０％～１１％）地氟醚在底物缓冲液不同钙离子浓度（０．４～２０μｍｏｌ／Ｌ）或反应温度（２５℃、３７℃）时，对质膜Ｃａ＾２＋－ＡＴＰａｓｅ活性的影响。结果 随地氟醚浓度的升高，质膜Ｃａ＾２＋－ＡＴＰａｓｅ活性逐渐下降。同一浓度地氟醚对Ｃａ＾２＋－ＡＴＰａｓ     

严重烧伤早期心肌收缩性与钙转运功能变化

目的研究烧伤早期心肌肌浆网（ＳＲ）钙转运功能变化，探讨其在烧伤后心肌收缩功能下降发病中的作用。方法采用３０％ＴＢＳＡⅢ度烧伤大鼠模型，离体心脏灌流，测定伤前及伤后心肌室内压最大变化速率（±ｄｐ／ｄｔｍａｘ）变化，制备心肌肌浆网，应用微孔滤膜过滤技术测定心肌ＳＲ４５Ｃａ２＋转运功能改变。结果与对照组相比，烧伤组左心室±ｄｐ／ｄｔｍａｘ明显降低（Ｐ＜０．０１），心肌ＳＲＣａ２＋－ＡＴＰａｓｅ活性及ＳＲ４５Ｃａ２＋摄取初速度、摄取容量均明显降低（Ｐ＜０．０１），偶联率比对照值大幅度下降。结论烧伤后早期心肌肌浆网Ｃａ２＋转运功能严重障碍，其是烧伤后心肌收缩功能降低的重要因素之一。     

严重烧伤早期心肌细胞内K~＋浓度和细胞膜Na~＋－K~＋－ATP酶活性的变化

为探讨严重烧伤后早期心肌细胞内Ｋ＋浓度的变化及其机制，采用Ｋ离子选择微电极技术，测定了大鼠３５％ＴＢＳＡⅢ度烧伤后第１、３、８和２４小时心室乳头肌细胞内Ｋ＋活度（并换算成浓度），同时测定了伤后８小时心肌细胞膜ＡＴＰ酶活性。结果表明：①严重烧伤后２４小时心肌细胞内Ｋ＋浓度均下降，伤后第１、３、８和２４小时分别降为正常值的９６．２％±１．３％、８５．８％±１．３％、６５．９％±１．０％和７３．７％±１．１％。伤后８小时达最低值，２４小时有所恢复，但仍低于伤后３小时水平；②伤后８小时心肌细胞膜总ＡＴＰａｓｅ，Ｍｇ２＋－ＡＴＰａｓｅ和Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ活性均降低。提示：烧伤促进Ｋ＋外流，抑制Ｋ＋内流，且烧伤后Ｋ＋内流减少与心肌细胞膜Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ活性显著降低有关。     

吗啡哌替啶芬太尼对离体人红细胞膜ATPases活性的影响

目的：比较研究吗啡、哌替啶、芬太尼对离体人红细胞膜ＡＴＰａｓｅｓ活性的影响。方法：将不同浓度的药物分别与人红细胞孵育，以孔雀绿－磷钼酸复合比色法测定ＡＴＰａｓｅｓ活性。结果：随着药物浓度的增加，吗啡对Ｎａ＋，Ｋ＋－ＡＴＰａｓｅ活性有增强作用（Ｐ＜０．０５），芬太尼则呈明显地抑制作用（Ｐ＜０．０５），哌替啶仅具有轻微抑制作用；吗啡能明显抑制Ｍｇ２＋－ＡＴＰａｓｅ和Ｃａ２＋，Ｍｇ２＋－ＡＴＰａｓｅ活性（Ｐ＜０．０１或Ｐ＜０．０５），但哌替啶和芬太尼对Ｍｇ２＋－ＡＴＰａｓｅ活性均无影响；这两种药物仅轻微地抑制Ｃａ２＋，Ｍｇ２＋－ＡＴＰａｓｅ活性。结论：应用大剂量吗啡或芬太尼时，需注意他们对人红细胞膜ＡＴＰａｓｅｓ活性的影响。     

冷血心肌麻痹液温度与保护效果关系的研究

目的：评价冷血心肌麻痹液（ＣＢＣ）心肌保护的温度效应关系。方法：离体工作鼠心模型,观察ＣＢＣ ４℃,８℃,１２℃,１６℃和２０℃停搏１２０分钟再灌注４５分钟对心功能,超微结构、心肌肌浆网（ＳＲ）Ｃａ＾２＋－ＡＴＰａｓｅ活性和Ｃａ＾２＋摄取恢复的改变。结果：４℃￣１２℃组心功能,超微结构及ＳＲ Ｃａ＾２＋－ＡＴＰａｓｅ活性和Ｃａ＾２＋摄取恢复均优于１６℃和２０℃组。结论：温度为影响ＣＢＣ心肌保护效果     

异丙酚和硫喷妥钠对离体大鼠心脏功能和细胞质膜Ca^2＋—ATPase活性的影响

目的 观察不同浓度异丙酚或硫喷妥钠对离体灌流大鼠心脏收缩力和心肌细胞质膜Ｃａ＾２＋－ＡＴＰａｓｅ活性的影响。方法 （１）以含不同浓度（１０ｕｍｏｌ／Ｌ～１０００ｕｍｏｌ／Ｌ）异丙酚或硫喷妥钠的克－汉二氏重碳酸盐缓冲液（ＫＨＢ）灌流离体大鼠心脏,测定心率（ＨＲ）、左室收缩压（ＬＶＳＰ）、左室收缩压上升最大速率（＋ｄｐ／ｄｔｍａｘ）和左室舒张压下降最大速率（－ｄｐ／ｄｔｍａｘ）。（２）参照文献制备大鼠心肌细胞质膜,观察不同浓度异丙酚或硫喷妥钠对质膜Ｃａ＾２＋－ＡＴＰａｓｅ活性的影响。结果 随着药液浓度的升高,异丙酚或硫喷妥钠使ＬＶＳＰ、＋ｄｐ／ｄｔｍａｘ逐渐降低,在等摩尔浓度的抑制作用异丙酚〉硫喷妥钠,高浓度的异丙酚或硫喷妥钠还可以减慢心率。异丙酚对质膜Ｃａ＾２＋－ＡＴＰａｓｅ活性的影响呈双相,低浓度（≤２０ｕｍｏ     

普鲁卡因对离体人红细胞膜ATPases活性的影响

盐酸普鲁卡因是静脉复合麻醉（ＩＢＡ）的常用药物之一。我们发现在ＩＰＢＡ下施行上腹部手 术时，术毕人红细胞膜ＡＴＰａｓｅｓ活性有所下降。本研究的目的是观察普鲁卡因对离体人红细胞膜ＡＴ－ Ｐａｓｅ活性是否有直接影响。结果；一定浓度的普鲁卡因对Ｎａ＋－Ｋ＋－ＡＴＰａｓｅ活性有明显抑制作用，对 Ｍｇ２＋－ＡＴＰａｓｅ活性无明显作用，对Ｃａ２＋－Ｍｇ２＋－ＡＴＰａｓｅ活性有轻微保护作用。研究结果为临床合理应 用ＩＰＢＡ提供了一定的实验依据。     

头部重点低温脱水综合治疗法对脑细胞膜功能的影响

作者采用“四血管”式兔脑缺血模型，观察了脑缺血３０分钟后再灌注３０，１８０和３６０分钟时脑细胞膜上Ｎａ＾＋，Ｋ＾＋－ＡＴＰａｓｅ，Ｃａ＾２＾＋－ＡＴＰａｓｅ，磷脂酶Ａ２和总磷脂的变化，比较了部重点低温，甘露醇脱水和头部重点低温水综合疗法对这些指标变化的影响。与正常动物比较，缺血再灌注后Ｎａ＾＋，Ｋ＾＋－ＡＴＰａｓｅ，Ｃａ＾２＾＋，Ｍｇ＾２＾＋－ＡＴＰａｓｅ活力进行性下降（Ｐ＜０．００１），磷脂酶Ａ     

烧伤后大鼠心肌组织唾液酸含量的变化

利用大鼠30%Ⅲ度烧伤模型,探讨了烧伤大鼠心肌组织唾液酸含量的变化,同时还观察了心肌组织三磷酸腺苷酶(ATPase)活性和 Ca~(2 )含量改变。结果表明:烧伤后大鼠心肌组织唾液酸显著降低,伤后3小时仅为对照组的58.8%。同时心肌组织 Na~ 、K~ -ATPase,Mg~(2 )-ATPase和 Ca~(2 )-ATPase 活性降低,而 Ca~(2 )含量明显升高。提示:唾液酸含量与心肌膜结构和功能有密切关系。组织唾液酸含量的减少可能是造成烧伤后能量代谢紊乱,ATPase 功能降低以及钙超载的重要因素之一。     

Effects of Panax notoginseng saponins on myocardial Gsalpha mRNA expression and ATPase activity after severe scald in rats

The aim of this study was to investigate the changes of myocardial Gsalpha mRNA expression and ATPase and the effects of Panax notoginseng saponins (PNS) on that after burns in rats. Wistar rats were exposed to a 95 degrees C water bath for 10s to produce 30% TBSA skin-full-thickness scalds. Myocardial Gsalpha mRNA level, cAMP content and adenyl cyclase (AC) activities were determined with dot blotting hybridization, radioimmunoassay and indirect method, respectively. The ATPase activities in plasma membrane of cardiomyocytes and erythrocytes were measured colorimetrically. At 3, 6, 9 hours after scalds, the myocardial Gsalpha mRNA expression decreased significantly (P<0.01). PNS (100, 200 mg kg(-1), i.p.) markedly increased these levels (P<0.01). The elevation was correlated significantly with PNS dose (r=0.95, P<0.05). At 3, 6, 9, 12, 24, 48 hour after the scalds, the myocardial cAMP content and AC basal activity was reduced significantly. PNS (100, 200 mg kg(-1), i.p.) increased cAMP content and enhanced AC activity markedly in comparison with the 3rd hour postburn group. The activities of (Ca(2+)-Mg(2+))-ATPase and (Na(+)-K(+))-ATPase in plasma membrane of myocardial cells and red blood cells in scald group were significantly lower than those in the normal control group (P<0.01). PNS (100 mg kg(-1), i.p.) improved these indexes significantly after scalds (P<0.01 or 0.05). These data suggested that the effects of PNS on myocardium in burned rats involved its action to increase myocardial Gsalpha mRNA expression and AC activity, cAMP content as well as ATPase activities.     

丙泊酚预处理对大鼠心肌缺血-再灌注损伤心肌细胞膜ATP酶活性的影响

目的 研究丙泊酚预处理对大鼠心肌缺血-再灌注损伤心肌细胞膜ATP酶活性及心肌组织形态学的影响.方法 40只雄性SD大鼠随机分成五组,每组8只:对照组(C组),缺血-再灌注组(IR组),丙泊酚1组(P1组),丙泊酚2组(P2组),丙泊酚3组(P3组).各组于再灌注60 min后立即取左室心尖部心肌,检测心肌匀浆中心肌细胞膜Na+-K+-ATP、Ca2+-Mg2+-ATP酶活性;光镜下观察心肌组织形态学变化.结果 IR时心肌细胞膜Na+-K+-ATP、Ca2+-Mg2+-ATP酶活性与C组相比明显下降(P<0.01);O1、P2、P3组心肌细胞膜Na+-K+-ATP、Ca2+-Mg2+-ATP酶活性与IR组相比明显升高,但仍低于C组(P<0.05).结论 丙泊酚可以减轻大鼠心肌缺血-再灌注损伤,其机制可能与恢复心肌细胞膜Na+-K+-ATP、Ca2+-Mg2+-ATP酶活性有关.     

大鼠肝缺血再灌注后肝细胞内糖原含量及细胞膜ATP酶活力的变化

目的 探讨肝细胞内糖原含量及细胞膜ATP酶活力与肝缺血再灌注(I/R)损伤的关系及相关机制.方法 健康雄性SD大鼠16只,随机分为2组(每组8只),①对照组:术中只分离肝周围韧带,不作肝门阻断及再灌注;②I/R组:进行45 min的部分肝门阻断及60 min的再灌注.取下腔静脉血2 mL,并迅速切取缺血肝组织.检测血清丙氨酸转氨酶(ALT)、门冬氨酸转氨酶(AST)、乳酸脱氢酶(LDH);测定肝组织中超氧化物歧化酶(SOD)、丙二七醛(MDA)、黄嘌呤氧化酶(XOD)、肝糖原、Na+K+-ATP酶、Ca2+-ATP酶、Mg2+-ATP酶等指标.结果 I/R组MDA、XOD较对照组升高;SOD、肝糖原、Na+K+-ATP酶、Ca2+-ATP酶下降(P<0.05).结论 肝I/R损伤与肝细胞生物能量缺乏、细胞膜离子泵功能障碍有关.     

Changes in erythrocyte membranes in burned rabbits

Eighteen white rabbits were subjected to a 30 per cent TBSA full thickness burn. Wound infection was found 9-13 days after injury and became severe a week or so later. ATPase activities, antioxidation ability, the proteins of erythrocyte membranes, and the Na+ contents of erythrocytes and serum were determined. The Ca++-ATPase activity was elevated during the first 17 days postburn, but showed a decline at the time of severe wound infection; the Na+,K+-ATPase activity showed peaks on postburn days 2 and 6, and then fluctuated above the preburn level. The change in Mg++-ATPase activity was similar to Na+,K+-ATPase. The erythrocyte Na+ content was increased, and the level of serum Na+ was decreased up to postburn day 6. Subsequently the erythrocyte Na+ was reduced and the serum Na+ increased up to day 17 postburn. The percentage of erythrocyte haemolysis in H2O2 was increased after the burn and became markedly so during wound infection, indicating that the antioxidation ability of burned rabbit erythrocytes was markedly impaired. During the period of wound infection, Coomassie blue-stained protein bands in SDS-polyacrylamide gel showed some changes in size and proportion in burned rabbits. For example, the second band was wider, the band 2 to band 1 ratio increased, and band 5 was smaller than before injury. These results seem to show that burn injury, especially when associated with sepsis, may affect both the structure and function of biological membranes.     

Ca2+-Mg2+-ATPase activity in kidney basolateral membrane in non-insulin-dependent diabetic rats. Effect of insulin

The direct effect of insulin on the high-affinity Ca2+-Mg2+-ATPase was studied in kidney proximal tubular basolateral membranes (BLM) obtained from control and streptozocin-induced non-insulin-dependent diabetes mellitus (NIDDM) rats. Plasma glucose of the diabetic animals was only mildly elevated (217 +/- 9 vs. 138 +/- 3 mg/dl). Both high- and low-affinity calcium-dependent Ca2+-Mg2+-ATPase activities were identified in the BLM. Enzyme activity in BLM from diabetic rats was higher at all Ca2+ concentrations tested due to a higher maximum velocity of the enzyme from NIDDM rats. The high-affinity Ca2+-Mg2+-ATPase activity was inhibited by trifluoroperazine (TFP) in both membranes. No difference in calmodulin content was found in the membranes from the diabetic and control rats. Insulin (16-200 microU/ml) significantly increased the high-affinity Ca2+-Mg2+-ATPase activity (17-40%) in membranes from control animals but had no effect on the enzyme activity in the membranes from the NIDDM rats. The basal activity of the enzyme at 0.1 microM free Ca2+ was higher in the BLM from the NIDDM animals compared to controls (17.8 +/- 0.5 vs. 14.7 +/- 0.8 nM Pi X mg-1 X min-1; P less than .02). There was no effect of insulin on the Ca2+-independent ATPase activity of BLM preparations. These findings demonstrate a defect in the ability of insulin to regulate the high-affinity Ca2+-Mg2+-ATPase activity in BLM from diabetic rats. Such a defect in enzyme activity may play a role in the mechanism of impaired insulin action observed in these NIDDM rats.     

ATPase activity and calcium uptake of microsomes isolated from stomach smooth muscle after exposure to phospholipase C

ATPase activity and Ca2+ uptake were examined in microsomal membrane fractions isolated from guinea pig stomach smooth muscle which had been exposed to phospholipase C (PLC). Basal Mg2+-ATPase, Na+, K+-ATPase and Ca2+, Mg2+-ATP activities were inhibited in a time dependent manner by PLC treatment. There was positive correlations between each of these ATPase activities and total phospholipid content of the microsomal fraction. Phosphotidylcholine restored Ca2+, Mg2+-ATPase activity of the microsomal fraction isolated from the tissue which had been treated with PLC for 30 min but not after 60 min. Ca2+ uptake in the presence of ATP by microsomal fraction from tissue treated with PLC for 60 min was significantly decreased. The results provide a cellular basis for the inhibitory effect of PLC on contractility of stomach smooth muscle.     

七氟醚后处理对大鼠心肌缺血再灌注时Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶活性的影响

目的 评价七氟醚后处理对大鼠心肌缺血再灌注时Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶活性的影响,探讨其减轻心肌缺血再灌注损伤的机制.方法 健康雄性Wistar大鼠45只,体重250～280 g,随机分为3组(n=15):假手术组(S组)、缺血再灌注组(I/R组)和七氟醚后处理组(Spo组).I/R组和Spo组采用结扎左冠状动脉前降支30 min时进行再灌注的方法制备心肌缺血再灌注模型,S组仅在左冠状动脉前降支下穿线.Spo组再灌注前1 min开始吸入2.5%七氟醚持续5 min.于再灌注2 h时取心肌组织,测定心肌梗死体积、Na+-K+-ATP酶活性和Ca2+-Mg2+-ATP酶活性.结果 与S组比较,I/R组心肌梗死体积扩大,心肌组织Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶的活性降低(P＜0.05);与I/R组比较,Spo组心肌梗死体积缩小,心肌组织Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶的活性升高(P＜0.05).结论七氟醚后处理可提高Na+-K+-ATP酶和Ca2+-Mg2+-ATP酶的活性,从而减轻大鼠心肌缺血再灌注损伤.     

Differential regulation of Ca2+-dependent ATPase-activity in left ventricular myocardium during mechanical circulatory support.

BACKGROUND: Myocardial recovery is observed in some end-stage heart failure patients after mechanical circulatory support. The sarcoplasmic reticulum Ca(2+)-adenosine triphosphatase (Ca2+-ATPase) activity is down-regulated in failing myocardium and contributes to heart failure-associated contraction/relaxation abnormalities. Regulation of Ca(2+)-ATPase after mechanical support was shown to be heterogeneous. Thus, we analyzed Ca(2+)-ATPase activity and protein expression in the paired myocardial samples of 21 patients supported by ventricular assist devices to identify factors that influence restoration of the Ca(2+)-transient after ventricular assist device support. METHODS: We measured Ca(2+)-ATPase activity using a reduced nicotinamide-adenine dinucleotide-coupled reaction, determined sarcoplasmic reticulum Ca(2+)-dependent ATPase protein using Western blotting, and determined 4-hydroxyproline using amino-acid analysis. RESULTS: The mean Ca(2+)-ATPase activity decreased at assist-device implantation and slightly increased at transplantation, but remained significantly lower than in non-failing donor hearts. However, individual responses were heterogeneous. Patients with older age, increased left ventricular diameter, and increased 4-hydroxyproline content showed down-regulation of Ca(2+)-ATPase activity, whereas we found up-regulation in patients with low values for these parameters after assist-device support. CONCLUSIONS: Sarcoplasmic reticulum Ca(2+)-ATPase activity, which influences the myocardial Ca(2+)-transient, generally is not restored to normal values in assist-device-supported hearts, but depends on a combined score of the left ventricular end-diastolic diameter, degree of ventricular fibrosis, and age of the patient at the time of assist-device implantation.     

Calcium induced the damage of myocardial mitochondrial respiratory function in the early stage after severe burns

OBJECTIVE: To explore the role of Ca(2+) in the damage to myocardial mitochondrial respiratory function in the early stage after severe burns. METHODS: An experimental model of 30%TBSA full-thickness skin scalding was reproduced in rats. Myocardial mitochondria were isolated from control and burned rats in the 1st, 3rd, 6th, 12th and 24th hour post-burn. The mitochondrial respiratory function, contents of mitochondrial calcium ([Ca(2+)](m)), activities of mtPLA(2), mtNOS, F(0)F(1)-ATPase and cytochrome c oxidase were determined. RESULTS: (1) At the 1st hour post-burn, [Ca(2+)](m) was increased significantly and the myocardial mitochondrial respiratory function was significantly reinforced. At the same time, mitochondrial respiratory control rate (RCR) was elevated and positively correlated with [Ca(2+)](m) (r=0.8415, P<0.01). At the 3rd, 6th, 12th and 24th hour post-burn, [Ca(2+)](m) increased further to a higher level, however, the mitochondrial respiratory function was decreased from the peak value at 6h, and RCR was negatively correlated with [Ca(2+)](m). (2) The activities of mtNOS and mtPLA(2) were higher significantly at the 3rd, 6th, 12th and 24th hour post-burn than that of the control. After severe burns, mtNOS and mtPLA(2) activities were both positively correlated with [Ca(2+)](m) (r=0.8945, P<0.05; r=0.9271, P<0.01, respectively). (3) The F(0)F(1)-ATPase synthetic activity increased at the 1st hour post-burn, but it decreased to 51.4, 44.9, 77.6 and 87.4% of that of the control at the 3rd, 6th, 12th and 24th hour post-burn respectively. The F(0)F(1)-ATPase hydrolytic activity decreased at the 1st hour post-burn and increased at the 3rd, however, it decreased again at the 6th, 12th and 24th hour post-burn. The activity of cytochrome c oxidase at the 3rd, 6th, 12th and 24th hour was low compared to the control. CONCLUSIONS: The changes of [Ca(2+)](m) were involved in damage to or regulation of mitochondrial respiratory function after severe burns. Appropriate increase of [Ca(2+)](m) reinforced the mitochondrial respiration at 1st hour after of burn injury, but Ca(2+) severe overload impairing F(0)F(1)-ATPase and cytochrome c oxidase directly, or, indirectly by activation of mtPLA(2) and mtNOS, might play an important role in damage to myocardial mitochondrial respiratory function at later stages after severe burns.