大鼠脊髓损伤后线粒体代谢功能和还原型谷胱甘肽水平的变化

目的 探讨大鼠脊髓损伤后伤段脊髓线粒体代谢功能和还原型谷胱甘肽(GSH)水平的变化.方法 取48只SD大鼠,随机分为假手术组(对照组)和脊髓损伤组(SCI组),每组又分为处理后6、12、24 h 3个时相组,每个时相组8只,分别提取伤段脊髓的线粒体,测定线粒体呼吸功能[呼吸Ⅲ态(R3)、呼吸Ⅳ态(R4)、呼吸控制率(RCR)及磷氧比(P/O)值]、三磷酸腺苷酶(ATPase)活性(Na+、K+-ATP酶和Ca2+、Mg2+-ATP酶活性)及GSH的变化.结果 SCI组在伤后6、12、24 h伤段脊髓线粒体的R3、RCR及P/O均显著低于对照组,R4显著高于对照组,差异有统计学意义(P＜0.05).SCl组Na+、K+-ATP酶和Ca2+、Mg2+-ATP酶较对照组明显降低,伤后6 h急剧下降,12 h后稍有代偿性升高,24 h后又下降,与对照组比较差异有统计学意义(P＜0.05).GSH水平SCI组与对照组相比明显降低,以伤后12 h最为明显,差异有统计学意义(P＜0.05).结论 脊髓损伤后伤段脊髓线粒体的呼吸功能、ATPase酶活性及GSH水平明显下降,说明脊髓损伤后线粒体能量代谢功能和自由基清除能力均受到明显损害.     

Mesenteric lymph duct ligation after hemorrhagic shock enhances the ATP level and ATPase activity in rat kidneys

Background: Kidney injury commonly occurs following hemorrhagic shock. This study aims to observe the effects of mesenteric lymph duct ligation (MLDL) on the adenosine triphosphate (ATP) levels and the cell membrane adenosine triphosphatase (ATPase) activity in the kidneys of rats subjected to hemorrhagic shock. Methods: Wistar rats were assigned into sham, shock, and ligation groups. The hemorrhagic shock model was established in the shock and ligation groups, and MLDL was performed in the ligation group after resuscitation. Renal homogenates were prepared to determine the ATP and ATPase levels at 90?min after hemorrhage and at 0, 1, 3, 6, 12, and 24?h after resuscitation. Results: The ATP levels, and the Na⁺–K⁺–ATPase, Mg²⁺–ATPase, Ca²⁺–ATPase, and Ca²⁺–Mg²⁺–ATPase activities in the renal tissue of the shock group were lower than those in the sham group at the multiple time points. Furthermore, the corresponding values in the ligation group were significantly higher than those in the shock group at multiple time points. Conclusion: MLDL improves energy metabolism and enhances the ATPase activity in the kidneys of hemorrhagic shock rats, along with other mechanisms that alleviate renal injury after hemorrhagic shock.     

AMPK对氧糖剥夺再灌注后小胶质细胞介导炎性反应的影响

目的：探讨氧糖剥夺再灌注（OGD／R）损伤后腺苷酸活化蛋白激酶（AM PK ）对小胶质细胞介导的炎性介质释放及信号传导的影响。方法培养BV2细胞株,应用OGD 6 h再灌注24 h建立缺血再灌注损伤离体模型,AICAR（5μmol／L、50μmol／L、100μmol／L）或 Compound C（0．1μmol／L、1μmol／L、10μmol／L）不同程度激活或抑制AMPK磷酸化,MTT法检测细胞活性,免疫印迹及ELISA方法,检测OGD／R后BV2细胞AMPK活性变化,以及对NF－κB信号通路中IκB磷酸化、TNF－α释放的影响。结果各浓度AICAR均能够促进OGD／R后BV2细胞存活（P ＜0．05）,抑制IκB磷酸化水平（P ＜0．05）,AICAR（100μmol／L）能够增加AMPK磷酸化水平（P ＜0．05）,抑制TNF －α的释放（P＜0．01）。而Compound C（10μmol／L）促进BV2细胞死亡（P＜0．01）,降低OGD／R后AMPK及IκB磷酸化水平（P ＜0．05）,促进 TNF －α释放（P ＜0．05）。结论 AMPK 磷酸化激活能够减轻OGD／R后BV2细胞介导的炎性损伤作用,而抑制AM PK磷酸化能够加重神经炎性反应。     

重症急性胰腺炎感染期CD4+ T淋巴细胞内ATP含量的变化

目的:探讨CD4+T淋巴细胞内三磷酸腺苷(ATP)含量在重症急性胰腺炎(SAP)感染期的变化。方法:将南开医院收治的42例SAP患者(SAP组)及36名健康志愿者(对照组)纳入研究。SAP组入院后于1,4,7,14,21 d用ImmuKnowTM免疫细胞功能测定试剂盒检测CD4+T淋巴细胞内ATP值,对照组以相同的时间间隔做相同的检测。之后根据SAP组是否进入感染期分为感染组(18例)和非感染组(24例)。分析和比较3组ATP含量的变化,并用受试者工作特征(ROC)曲线分析ATP含量变化对判断SAP继发感染的价值。结果:对照组CD4+T淋巴细胞ATP含量保持稳定。两个SAP组的ATP含量变化趋势基本一致,入院后第1,4天两组的ATP含量明显高于对照组(P<0.05),第7天两组ATP含量明显降低,均于第14天降至最低水平,其中感染组下降程度明显大于非感染组(P<0.05),随后两组ATP含量开始回升,第21天非感染组ATP含量已基本接近对照组,但感染组仍低于对照组(P<0.05)。ROC曲线分析表明,当CD4+T细胞内ATP值降低(<151.55 ng/mL)时,SAP继发感染的机率明显增加;ATP含量的降低对判断SAP继发感染的敏感度为0.810,特异度为0.605。结论:CD4+T淋巴细胞内ATP含量可较准确地反映SAP患者的整体细胞免疫功能状况和继发感染的风险。     

二甲双胍对异氟醚麻醉小鼠血糖的影响

目的 观察二甲双胍对异氟醚麻醉小鼠血糖的影响.方法 156只8周龄雄性C57BL/6小鼠分两部分进行实验.①血糖检测:这部分实验分两步进行.首先,28只小鼠按照按随机数字表法分为未禁食组(n组)和禁食12 h组(f组);各组再分为2个亚组,对照组(Cn组/Cf组),麻醉组(An组/Af组).进一步实验使用56只小鼠按随机数字表法分为n组和f组,每组28只.两组均再按随机数字表法分为4个亚组,Cn组/Cf组,An组/Af组,二甲双胍组(Mn组/Mf组)和二甲双胍麻醉组(MAn组/MAf组),每亚组均为7只.Mn组、Mf组、MAn组和MAf组于麻醉前1.5 h腹腔注射二甲双胍40 mg/kg,An组、Af组、MAn组和MAf组均行异氟醚6h麻醉.通过尾静脉取血检测围麻醉期各时间点血糖值.②荧光定量核酸扩增检测系统(quantitative polymerase chain reaction detecting system,Q-PCR)检测:共72只小鼠.各亚组分组方法同上,分别于麻醉1、4、6h取材下丘脑,每组每个时间点取3只.Q-PCR检测腺苷酸活化蛋白激酶(adenosine monophosphate activated protein kinase,AMPK)两个亚型AMPKα1、AMPKα2的mRNA表达水平.结果 血糖水平变化:与n组比较,f组小鼠血糖显著降低[(8.25±1.02) mmol/L比(6.46±0.65) mmol/L,P＜0.05].在f组和n组中,麻醉组小鼠均出现血糖水平升高;与Cn组和Cf组比较,An组和Af组分别在麻醉0.5、1、2h和1、2、3h升高(P＜0.05);分别与Cn组和Cf组比较,Mn组和Mf组血糖水平差异无统计学意义(P＞0.05);MAn组和MAf组均于麻醉2h开始出现低血糖并持续(P＜0.05),这种差异分别在麻醉结束4h和1h后消失.下丘脑AMPK mRNA表达:1h,与Cf组比较,MAf组AMPKα1和AMPKα2mRNA表达下调(P＜0.05);4h,与Cn组和Cf组比较,An组、MAn组和Af组AMPKα1表达下调(P＜0.05),AMPKα2 mRNA表达在MAf组降低(P＜0.05);6h,与Cn组和Cf组比较,AMPKα1和AMPKα2在An组和MAn组、Af组和MAf组mRNA表达都降低(P＜0.05).结论 长时程异氟醚麻醉可使小鼠血糖呈“先高后低”改变,二甲双胍预处理后麻醉小鼠可出现持续低血糖,这一过程与下丘脑AMPK转录活性无明显关联.     

负荷-静息99Tcm-MIBI门控心肌灌注断层显像相位分析评价左室缺血心肌收缩同步性

目的 以99 Tcm-MIBI门控心肌灌注断层显像(GSMPI)相位分析探讨不同缺血灌注状态下左室心肌收缩同步性.方法 回顾性分析129例[男65例,女64例,年龄48～88(68.6±10.2)岁]行99 Tcm-MIBI两日法静息-负荷GSMPI患者的心肌灌注及心功能数据.采用17节段5分制对图像进行评分,获得负荷总积分及心肌缺血积分,分为灌注正常组及灌注异常组,后者再分为可逆性灌注缺损组及固定性灌注缺损组.采用两独立样本t检验比较分析各组间GSMPI的PSD和PHB,各组内静息与负荷PSD及PHB间差异的比较采用配对t检验.结果 129例患者中,灌注正常组66例,灌注异常组63例,其中可逆性灌注缺损组39例,固定性灌注缺损组24例.灌注异常组PSD及PHB显著大于灌注正常组,分别为18.3±7.8和14.3±6.6,68.6±30.9和50.2±20.0(t=-3.110和-3.989,均P＜0.05).尽管固定性灌注缺损组的PSD和PHB较可逆性灌注缺损组有增大趋势,但差异均无统计学意义(=-1.554～-0.408,均P＞0.05);两亚组静息和负荷PSD和PHB间亦无明显差异(t=-0.961 ～-0.114,均P＞0.05).LVEF≤60％组的静息和负荷PSD(20.4±8.1和20.8±6.4)均显著大于LVEF＞ 60％组(15.0±6.8和15.3±7.0;t=3.642和3.886,均P＜0.05);LVEF≤60％组的静息和负荷PHB (77.8±53.5和78.4±26.7)也显著大于LVEF＞60％组(53.5±23.0和55.9±24.5;t=4.567和4.302,均P＜0.05).结论 99Tcm-MIBI GSMPI相位分析能够反映血流灌注异常对心肌收缩同步性的损害及由此造成的对左室整体收缩功能的影响,可在一定程度上反映不同心肌缺血状态下左室收缩同步性的差异;就99Tcm-MIBI而言,负荷和静息GSMPI相位分析对左室收缩同步性评估的价值相当.     

Strain-Encoded Cardiac Magnetic Resonance for the Evaluation of Chronic Allograft Vasculopathy in Transplant Recipients

The aim of our study was to investigate the ability of Strain-Encoded magnetic resonance imaging (MRI) to detect cardiac allograft vasculopathy (CAV) in heart transplantation (HTx)-recipients. In consecutive subjects (n = 69), who underwent cardiac catheterization, MRI was performed for quantification of myocardial strain and perfusion reserve. Based on angiographic findings subjects were classified: group A including patients with normal vessels; group B, patients with stenosis <50%; and group C, patients with severe CAV (stenosis ≥ 50%). Significant correlations were observed between myocardial perfusion reserve with peak systolic strain (r =−0.53, p < 0.001) and with mean diastolic strain rate (r = 0.82, p < 0.001). Peak systolic strain and strain rate were significantly reduced only in group C, while mean diastolic strain rate and myocardial perfusion reserve were already reduced in group B and A. Myocardial perfusion reserve and mean diastolic strain rate had higher accuracy for the detection of CAV (AUC = 0.95, 95% CI = 0.87–0.99 and AUC = 0.93, 95% CI = 0.84–0.98, respectively) and followed peak systolic strain and strain rate (AUC = 0.80, 95% CI = 0.69–0.89 and AUC = 0.78, 95% CI = 0.67–0.87, respectively). Besides the quantification of myocardial perfusion, the estimation of the diastolic strain rate is a useful parameter for CAV assessment. In combination with the clinical evaluation, these parameters may be effective tools for the routine surveillance of HTx-recipients.     

钙网蛋白在不同预处理心肌细胞缺血再灌注的保护作用

目的 观察3种不同预处理对在体缺血再灌注心肌的保护作用,探讨钙网蛋白(CRT)在预处理心肌细胞缺血再灌注损伤的作用.方法 将30只成年SD大鼠随机分成5组(n=6),分别为缺血再灌注组、缺血预处理组、腺苷预处理组、远程预处理组和假手术组.建立大鼠在体缺血冉灌注损伤模型,观察各组缺血再灌注前后心功能变化,并检测再灌注末血清肌钙蛋白T(cTnT)、丙二醛(MDA)、超氧化物歧化酶(SOD)的变化以及心肌组织CRT的表达.结果 缺血预处理组、远程预处理组与缺血再灌注组比较(±dp/dt max)有明显提高(P<0.05).缺血预处理组、腺苷预处理组、远程预处理组cTnT、MDA值均低于缺血再灌注组,SOD值高于缺血再灌注组(P<0.05);腺苷预处理组SOD值高于缺血预处理组和远程预处理组,cTnT值则低于后2组(P<0.05);缺血预处理组、腺苷预处理组、远程组与缺血再灌注组比较,CRT表达灰度值均显著降低(P<0.05).结论 腺苷预处理、远程预处理均可以模拟缺血预处理的心肌保护作用;预处理可能通过下调钙网蛋白高表达减轻在体大鼠心肌细胞缺血再灌注损伤.     

Effects of intravenous adenosine 5′-triphosphate on intraoperative hemodynamics and postoperative pain in patients undergoing major orofacial surgery: a double-blind placebo-controlled study

Purpose  We conducted a double-blind placebo-controlled study to investigate the effects of the intraoperative intravenous infusion of adenosine 5′-triphosphate (ATP) on intraoperative hemodynamics and postoperative pain in patients undergoing major orofacial surgery. Methods  Thirty patients (age, 16–42 years; 16 males/14 females) scheduled for sagittal split ramus osteotomy were assigned in a double-blind fashion to receive intraoperative intravenous infusion of ATP (n = 15) or saline (n = 15). Anesthesia was induced and maintained with propofol, fentanyl, and vecuronium. Local anesthesia was added for intraoperative analgesia. In the ATP group, ATP was infused at a rate of 160 μg·kg⁻¹·min⁻¹ throughout surgery. Postoperative pain was managed with intravenous patient-controlled analgesia (PCA) with morphine. The intensity of postoperative pain was assessed with a verbal numeric rating scale (NRS). Morphine consumption was also assessed. Results  There were no differences in demographic, anesthetic, and surgical data between the ATP and placebo groups. Intraoperatively, ATP effectively suppressed responses of blood pressure and heart rate to painful surgical stimuli. There were no differences in postoperative NRS scores between the two groups. However, postoperative morphine consumption was significantly less in the ATP group, compared with the placebo group, throughout the 72-h postoperative observation period. Cumulative morphine consumption for 72 h postoperatively was 47% less with ATP, compared with placebo. No adverse effect of ATP was observed. Conclusion  Our data suggest that intraoperative ATP infusion can blunt hemodynamic responses to surgical stimuli and produce prolonged analgesia in patients undergoing major orofacial surgery.     

大鼠嘌呤P2Y2受体在神经系统分布的实验研究

目的探讨P2Y2受体在脊髓、背根神经节和坐骨神经的表达和具体分布，研究三磷酸腺苷（adenosine triphosphate．ATP）对神经再生的作用机制提供理论基础。方法将6只SD乳鼠的脊髓、背根神经节和坐骨神经标本置于含有0．1％二乙基焦碳酸的4%多聚甲醛液中快速固定、石蜡包埋、超薄切片。实验组：根据P2Y2受体mRNA的碱基序列，制作非放射性标记的核苷酸探针，原位杂交后将切片置于含有NBT溶液（50mg／ml硝基兰四唑溶于二甲基甲酰胺）、BCIP溶液（75mg／ml溴绿一吲哚磷酸溶于二甲基酰胺）的检测缓冲液中染色，镜下观察P2Y2受体的具体分布。对照组：切片刚不含探针的杂交缓冲液覆盖、染色观察。结果实验组：脊髓灰质前角神经元胞浆中可见P2Y2受体的表达，呈弱阳性；背根神经节雪旺细胞的胞浆和胞核中均可见P2Y2受体的表达，且呈强阳性；对照组：无P2Y2受体表达。实验组与对照组坐骨神经原位杂交尢P2Y2受体的表达。结论P2Y2受体主要分布在脊髓、背根神经节，细胞外ATP可以通过P2Y2受体作用于脊髓和背根神经节细胞。