ATP-MgCl2 treatment after experimental acute myocardial ischemia and reperfusion

BACKGROUND: The effect of ATP-MgCl2 on myocardial metabolism and hemodynamics was investigated in this study. METHODS: Twelve dogs were entered in this research. Six dogs received ATP-MgCl2 and the remaining dogs were considered as controls. The amount of ATP and MgCl2 concentration of this solution is 100 mumol/ml each. The volume administered to the animals during the aortic occlusion is 0.25 ml/kg/hour; in the solution are 100 mumol/ml dose each. The volume administered to the animals during reperfusion is 0.25 ml/kg/hour. The left anterior descending artery was occluded for a period of one hour and the drug was administered during reperfusion. RESULTS: Three hours after reperfusion, cardiac output was 1524 +/- 26 ml/min in the control group and 1638 +/- 47 ml/min in the ATP-MgCl2 group (p < 0.05), pulmonary capillary wedge pressure was 14 +/- 3 in the control group and 8 +/- 2 in the ATP-MgCl2 group. At the same time interval tissue ATP and lactate level was 7 +/- 3, 1.3 +/- 0.4 in the control group and 14 +/- 2, 0.0 +/- 0.2 in the ATP-MgCl2 group respectively (p < 0.05). CONCLUSIONS: In this study we demonstrated that ATP-MgCl2 usage after one hour of arterial occlusion protects the heart from the adverse effects of ischemia/reperfusion.     

Effects of ATP-MgCl2 administration in hypovolemic dogs

BACKGROUND: The aim of the study was to evaluate the efficacy of ATP-MgCl2 on myocardial insufficiency associated with hypovolemic shock in dogs. We designed the study as a controlled randomized study. METHODS: Six mixed-breed dogs weighing 22 +/- 3 kg were included in the control group and 20 +/- 3 kg in the ATP-MgCl2 group. After the animals were anesthetized 40 ml/kg of blood was withdrawn in 15 minutes. Animals were observed for 45 minutes after removal of blood. Six animals received 45 ml/kg of lactated Ringer's solution and the other animals were treated with 45 ml/kg of lactated Ringer's solution and ATP-MgCl2. All measurements were made before removal of blood, 45 min after exsanguination and at 1 hour intervals for 3 hours. The following parameters were measured; systemic and pulmonary arterial pressures, pulmonary capillary wedge pressure, central venous pressure, cardiac output, rectal temperature, arterial pH, PCO2 and PO2 and mixed venous hemoglobin oxygen saturation. In addition blood samples were collected for the analysis of lactate and tumor necrosis factor (TNF) concentrations. RESULTS: After hemorrhage, cardiac index (CI) decreased significantly from 122 +/- 9 to 52 +/- 9 ml/kg/min in the control group (p < 0.0001) and from 124 +/- 11 ml/kg/min to 50 +/- 6 ml/kg/min in the ATP-MgCl2 group, respectively (p < 0.0001). After volume replacement, Cl was 93 +/- 6 ml/kg/min in the control group and 111 +/- 4 ml/kg/min in the ATP-MgCl2 group 3 hours after the onset of reinfusion, respectively (p < 0.05). TNF was 36 +/- 5 pg/ml in the control group and 21 +/- 3 pg/ml in the ATP-MgCl2 group (p < 0.05). Three hours after the onset of hemorrhagic shock, oxygen consumption and delivery were 126 +/- 14 and 206 +/- 19 ml/min in the control group and 198 +/- 16 and 305 +/- 27 ml/min in the ATP-MgCl2 group, respectively. At the same time point the oxygen extraction ratio was 0.49 +/- 0.04 in the control group and 0.61 +/- 0.03 in the ATP-MgCl2 group (p < 0.01). CONCLUSIONS: Hemorrhagic shock causes TNF release which may cause multiple organ failure. Organ dysfunction still persists even after the appropriate treatment. ATP-MgCl2 attenuates the release of TNF which may improve the adverse effects of hemorrhagic shock.     

三磷酸腺苷-氯化镁对新生大鼠高氧肺损伤的影响

目的:探讨三磷酸腺苷-氯化镁(ATP-MgCl2)对高氧诱发新生鼠肺损伤的影响。方法:选用生后2天体重5～10 g的Wistar大鼠120只,随机分为空气对照组、高氧模型组、ATP-MgCl2治疗组,每组40只。新生鼠制备成高氧模型后第2天始治疗组新生鼠腹腔内注射ATP-MgCl2(45 mg/kg),空气对照组和高氧模型组腹腔内注射等量生理盐水,以上3组实验开始第3、7及14天每组处死10只动物,取肺组织,光镜下观察肺组织的病理变化,采用免疫组化染色观察肺组织中肿瘤坏死因子-a(TNF-a),转化生长因子(TGF-β1)和波形蛋白(Vimentin)的表达。结果:高氧模型组TNF-a、TGF-β1及Vim-entin表达强度明显高于空气对照组,差异有统计学意义(P<0.01)。ATP-MgCl2组TNF-a、TGF-β1及Vimentin表达强度低于高氧模型组,差异有统计学意义(P<0.05)。结论:三磷酸腺苷-氯化镁对新生大鼠高氧肺损伤有保护作用,对支气管肺发育不良有一定的预防作用。     

Effect of exogenous DMNPE-caged ATP on in vitro-matured bovine oocytes prior to parthenogenetic activation, fertilisation and nuclear transfer

Adenosine triphosphate (ATP) plays an important role during fertilisation of the mammalian oocyte through its ability to alter the frequency and duration of calcium oscillations. It has also been shown that higher ATP levels correlate with increased developmental competence in bovine and human oocytes. During somatic cell nuclear transfer (NT), the incoming nucleus is remodelled extensively, undoubtedly using a variety of ATP-dependent enzymes. The aim of the present study was to determine whether additional exogenous ATP influences activation of parthenogenetic (PA), in vitro-fertilised (IVF) or cloned (NT) in vitro-matured bovine oocytes. Blastocyst development and cell numbers in PA embryos were found to increase in a dose-dependent manner following the photorelease of 0, 50, 100, 500 and 1000 microm DMNPE-caged ATP (adenosine 5'-triphosphate, P3-(1-(4,5-dimethoxy-2-nitrophenyl)ethyl) ester, disodium salt). No cleavage was found following release of 2 and 5 mm DMNPE-caged ATP or with DMNPE-caged ATP (not photoreleased). There were also no differences in blastocyst rates or cell numbers between the control group and groups treated with caged, but not photoreleased, ATP. The addition of exogenous ATP before IVF or to NT couplets did not result in a significant increase in blastocyst development or cell number. Embryo transfer is necessary to determine whether exogenous ATP can positively affect reprogramming, resulting in higher cloned pregnancy rates or live-term births.     

三种代谢综合征诊断标准在2型糖尿病家系人群中应用比较

目的 比较2005年美国国家胆固醇教育计划成人治疗方案第3次报告(ATPⅢ)、2005年国际糖尿病联盟(IDF)和2004年中华医学会糖尿病学分会(CDS)建议的代谢综合征(MS)诊断标准在2型糖尿病家系人群中应用的差异.方法 对715个2型糖尿病家系中有完整血压、血脂及血糖资料的4468名成员(包括配偶),由专门小组调查并采血样后,分别用ATPⅢ、IDF和CDS标准诊断MS,并比较MS患病率及诊断的一致性.结果 ATPⅢ、IDF和CDS标准诊断出的家系成员MS患病率分别为44.94%(2008/4468)、37.87%(1692/4468)、23.86%(1066/4468),均呈二级亲、配偶、一级亲、先证者逐渐升高的趋势[ATP Ⅲ标准诊断MS患病率分别为23.78%(117/492)、35.77%(318/889)、45.40%(1077/2372)、69.37%(496/715);IDF标准诊断MS患病率分别为20.53%(101/492)、31.61%(281/889)、38.74%(919/2372)、54.69%(391/715);CDS标准诊断MS患病率分别为8.94%(44/492)、16.99%(151/889)、25.08%(595/2372)、38.60%(276/715);ATPⅢ:X2趋势=266.359;IDF:X2趋势=155.950;CDS:X2趋势=165.087;P值均<0.01].用ATPⅢ、IDF诊断时,MS患病率女性明显高于男性[ATPⅢ:47.47%(1156/2435)、41.91%(852/2033);IDF:43.00%(1047/2435)、31.73%(645/2033);X2>值分别为13.871、60.169,P值均<0.01],而用CDS标准诊断时女性低于男性(分别为22.38%、25.63%,X2=6.423,P=0.011).ATPⅢ与IDF、ATPⅢ与CDS、IDF与CDS标准两两间的一致检出率分别为92.93%、75.56%和77.21%,其Kappa值分别为0.855、0.484和0.478(P值均<0.01).结论 在2型糖尿病家系人群中,ATPⅢ标准诊断的MS患病率及检出危险因素聚集的比例最高,更能反映该人群MS及其组分的特点.     

活性氧在氯化锰致PC12细胞凋亡中的作用

目的 探讨活性氧（ROS）在氯化锰（MnCl2）诱导PC12细胞凋亡中的作用机制.方法 构建MnCl2诱导的PC12细胞模型,MTT法检测细胞存活率,流式细胞分析PC12细胞凋亡率;琼脂糖凝胶电泳检测DNA片段化程度;分光光度法检测培养基中活性氧（ROS）生成量变化;化学发光法检测细胞三磷酸腺苷（ATP）生成量和Caspase-3表达量的变化;RT-PCR法检测凋亡相关基因bcl-xl和bax的表达.结果 PC12细胞存活率与MnCl2诱导浓度和诱导时间呈负相关（P＜0.01）;2 mmol/L MnCl2诱导PC12细胞36 h,细胞凋亡率明显上升（P＜0.01）;核DNA发生明显片段化;细胞ROS生成量明显增加（P＜0.001）,细胞ATP生成量受到明显抑制（P＜0.01）;基因bcl-xl表达被抑制,bax表达上升（P＜0.01）;Caspase-3在细胞凋亡中被激活（P＜0.01）.结论 MnCl2诱导的PC12细胞凋亡与ROS升高、线粒体功能破坏和激活Caspase-3有关.     

Hydrogen sulfide contributes to hypoxia-induced radioresistance on hepatoma cells

Growing evidence has demonstrated that, as an endogenous signaling gasotransmitter, hydrogen sulfide (H(2)S) plays an important role in regulating numerous biological functions. The role of H(2)S in hypoxia-induced radioresistance on hepatoma cells was investigated in the present work. Results showed that, when HepG2 cells were maintained in hypoxia circumstances for 4 h, the cellular radioresistance was extensively increased so that the oxygen enhancement ratio of the survival fraction approached 2.68. Under this hypoxic condition, when the cells were treated with DL-propargylglycine (PPG) and aminooxyacetic acid (AOAA), a specific inhibitor of H(2)S synthase of cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS) respectively, radiation responses including cell killing, micronuclei (MN) formation, and caspase-3 activity were significantly enhanced. However, treatment of cells with low concentrations of NaHS (≤ 100 μM) protected cells from these radiation damages. Western bolting assay showed that CSE and CBS were over-expressed in the irradiated hypoxic cells in a dose dependent manner. Moreover, when the hypoxic HepG2 cells were treated with NaHS together with glibenclamide, a specific inhibitor of K(+)(ATP) channels, the role of exogenous H(2)S in radioprotection was partly eliminated. This study demonstrated that H(2)S contributed to hypoxia-induced radioresistance probably via the opening of K(+)(ATP) channels, which suggests that the endogenous H(2)S synthase could be a potential radiotherapeutic target for a hypoxic tumor.     

ATP生物荧光检测法在提高手术室人员手卫生依从性的研究

目的 探讨ATP生物荧光法对手术室各类人员进行手卫生依从性的影响.方法 采用现场观察法,观察应用ATP生物荧光法进行现场监测前后手术室各类人员进行手卫生的次数;应用ATP生物荧光法与细菌培养计数分别监测人员手卫生效果,并将观察结果进行比较.结果 应用ATP生物荧光检测法进行现场快速监测.后,手术室各类人员进行手卫生依从性由应用前的81.23％提高至应用后的92.89％ (P＜0.01),手卫生合格率由应用前81.11％提高至应用后的93.33％(P＜0.05),差异均有统计学意义.结论 ATP生物荧光法能提高各类人员手卫生依从性和现场监管力度,确保手术患者的安全.     

Identification of a P2X7 receptor in GH(4)C(1) rat pituitary cells: a potential target for a bioactive substance produced by Pfiesteria piscicida

We examined the pharmacologic activity of a putative toxin (pPfTx) produced by Pfiesteria piscicida by characterizing the signaling pathways that induce the c-fos luciferase construct in GH(4)C(1) rat pituitary cells. Adenosine-5'-triphosphate (ATP) was determined to increase and, at higher concentrations, decrease luciferase activity in GH(4)C(1) rat pituitary cells that stably express c-fos luciferase. The inhibition of luciferase results from cytotoxicity, characteristic of the putative P. piscicida toxin (pPfTx). The actions of both pPfTx and ATP to induce c-fos luciferase were inhibited by the purinogenic receptor antagonist pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS). Further characterization of a P2X receptor on the GH(4)C(1) cell was determined by the analog selectivity of P2X agonists. The P2X1/P2X3 agonist alpha,beta-methylene ATP (alpha,beta-MeATP) failed to increase or decrease c-fos luciferase. However, the P2X7 agonist 2',3'-(4-benzoyl)benzoyl ATP (BzATP), which had a predominant cytotoxic effect, was more potent than ATP. Immunoblot analysis of GH(4)C(1) cell membranes confirmed the presence of a 70-kDa protein that was immunoreactive to an antibody directed against the carboxy-terminal domain unique to the P2X7 receptor. The P2X7 irreversible antagonist oxidized-ATP (oxATP) inhibited the action of ATP, BzATP, and pPfTx. These findings indicate that GH(4)C(1) cells express purinogenic receptors with selectivity consistent with the P2X7 subtype and that this receptor pathway mediates the induction of the c-fos luciferase reporter gene by ATP and the putative Pfiesteria toxin     

Mechanism of refractory ceramic fiber- and rock wool-induced cytotoxicity in alveolar macrophages

OBJECTIVES: Man-made vitreous fibers (MMVFs) can induce cytotoxicity in a way similar to that of other particles, including silica and asbestos fibers. However, as yet the mechanism of MMVF-induced cytotoxicity is still not clear. This report aims to clarify the mechanism of MMVF-induced cytotoxicity in the alveolar macrophage (AM). In this mechanism, an attempt to prove the involvement of the adenosine triphosphate (ATP) generation system and the polyinosinic acid-inhibitable scavenger receptors was made. METHODS: Several parameters were observed for cytotoxicity, such as cell viability, the release of lactic dehydrogenase (LDH) and ATP levels in rat AM's that were treated with refractory ceramic fibers (RF2) and rock wool (RW1). A specially designed ATP generation system was used to determine the effect of MMVF on ATP generation. A scavenger receptor ligand was applied to evaluate the relationship between scavenger receptors and MMVF-induced ATP depletion. RESULTS: A 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium bromide (MTT) assay indicated that both RF2 and RW1 caused a decrease in cell viability and this decrease was concentration-dependent. RF2 and RW1 increased the release of LDH with increasing fiber concentration. From these parameters, RF2 was shown to exhibit greater cytotoxicity than did RW1. Both fibers decreased the intracellular ATP content and this decrease was concentration-dependent. The decrease was more pronounced in RW1 than in RF2 at all fiber concentrations. These fibers suppressed succinate-triggered oxygen consumption. Polyinosinic acid, a ligand of the scavenger receptor, inhibited the MMVF-induced decrease in ATP concentration. CONCLUSION: These results suggest that RF2 and RW1 can induce cytotoxicity and ATP depletion in the AM through the polyinosinic acid-inhibitable scavenger receptor. ATP depletion was the important factor in MMVF cytotoxicity, especially by RW1.