L-丙酰肉碱对再灌注心肌损伤的保护及体外抗自由基作用

目的:观察L－丙酰肉碱对缺血再灌注心肌的保护作用，并探讨其机理。方法：采用大鼠在体心脏冠状动脉前降支阻断5min造成缺血再灌注模型，持续心电监护，观察心律失常与心功能指标；应用电子顺磁共振观察L－丙酰肉碱对Fenton体系及二甲基亚砜（DMSO）碱性有氧体系产生自由基的作用。结果：L－丙酰肉碱静脉给药明显减少再灌注时室性心动过速、室性纤维颤动的发生（P＜0．05），促进再灌注后左室收缩压、左室压最大上升速率、左室压最大下降速率、心力环面积的恢复，与对照组相比，各参数均明显增高（P＜0．05）；静脉注射L－丙酰肉碱100mmol／L时促进Fenton体系OH的产生，而500mmol／L时产生明显抑制作用，L－丙酰肉碱明显抑制DMSO碱性有氧体系OS的产生。结论：L－丙酰肉碱明显减少再灌注心律失常的发生，促进再灌注后心功能的恢复。推测它对自由基的作用可能是再灌注损伤保护机理之一。     

MISE AU POINT D'UNE TECHNIQUE D'ADMINISTRATION IN VIVO DES VECTEURS GENETIQUES DANS LEMUSCLE CARDIAQUE

Objective In order to improve the in vivo gene transfer into the heart muscle, we have designed a ECG-synchronized microinjection system that allows sequential gene delivery to the myocardium.Methods A cannula was introduced into the right carotid artery of the Wistar rat under general anesthesia.With the ECG-synchronized injection during diastole, the genetic vector (Ad CMV lacZ ) infusion was performed with various concentrations( l07 ～ l010pfu ) and different frequency ( the ratio of heart beats per injection from 1: 1 to 4: 1 ). The hearts of the rats were removed after 7 days for histological examination. Results Best results were obtained with a total vector amount of l09 pfu and a good ratio 3: 1 between heart frequency and injection frequency. The transfection efficiency was increased by use of vasodilators and by an increase of vascular permeability. No signs of myocardial ischemia or ventricular arrythmia were observed. Conclusion We have established a novel and safe method for in vivo gene transfer into the heart. Transgene expression suggests that this method may be useful technique to study cardiac function of treat cardiac diseases by means of gene theratpy.     

异丙酚与安氟醚或七氟醚静吸复合麻醉对心肌酶的影响

目的:观察异丙酚与安氟醚或七氟醚静吸复合麻醉对心肌酶的影响.方法:32例择期非心脏手术的全麻病人,随机分为4组(每组8例),分别给予安氟醚麻醉(A组)、七氟醚麻醉(B组)、异丙酚-安氟醚麻醉(C组)、异丙酚-七氟醚麻醉(D组).其中A、B组为对照组,C、D组为观察组.分别于麻醉前、麻醉诱导后2 h和术后3 d采集静脉血测血清磷酸肌酸激酶(CK)及其同功酶(CK-MB)、天门冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(HBDH).结果:麻醉诱导后2 h,A组CK、CK-MB值、LDH及HBDH值升高,与麻醉前比较差异有显著性(P<0.01或P<0.05);B组CK和CK-MB值升高,与麻醉前比较差异有显著性(P<0.05或P<0.01).术后3 d,A、B两组CK值升高,与麻醉前和麻醉诱导后2 h比较差异有显著性(P<0.01或P<0.05),AST值升高,与麻醉前比较差异有显著性(P<0.01或P<0.05).而且A、B两组相比较,A组的CK、LDH值升高幅度明显大于B组(P<0.05).C、D两组仅CK值在术后3 d与麻醉前比较差异均有显著性(P<0.01),但其升高幅度均明显低于A、B两组的同时值(P<0.01),其余各项心肌酶的变化在麻醉诱导后2 h及术后3 d差异均无显著性(P>0.05).与C组比较,A组在麻醉诱导后2 h CK、CK-MB、HBDH值升高(P<0.01),LDH值升高(P<0.05);在术后3 d CK值升高(P<0.01).与D组比较,B组CK值在麻醉诱导后2 h及术后3 d升高(P<0.01),CK-MB值在麻醉诱导后2 h升高(P<0.05).结论:安氟醚和七氟醚两者均能使心肌酶升高,但安氟醚所致的心肌酶升高幅度更明显;临床麻醉剂量的异丙酚能有效地防止安氟醚和七氟醚麻醉时心肌酶的升高.     

幼兔缺血预处理在心肌保护第二窗期对未成熟心肌Bcl-2基因mRNA表达的影响

目的　观察幼兔心脏缺血预处理 2 4h对未成熟心肌缺血 /再灌注后Bcl -2mRNA表达的影响 ,探讨未成熟心肌保护第二窗形成的作用机理。方法　 18只 3～ 4周龄幼兔 ,随机分为 3组 ,每组 6只 :Ⅰ组 ,正常对照组 ;Ⅱ组 ,缺血 /再灌注损伤组 ;Ⅲ组 ,缺血预处理组。建立活体心脏缺血 /再灌注损伤模型 ,Maclab/8s系统监测左心室发展压 (LVDP)、左室压上升及下降最大速率 (+dp/dtmax,-dp/dtmax)变化 ,原位免疫杂交 (ISH)方法检测心肌细胞内Bcl-2mRNA的表达。结果　缺血再灌注前 ,各组间LVDP、±dp/dtmax无显著性差异 (P >0 .0 5) ;再灌注 1h后 ,Ⅱ组的LVDP、+dp/dtmax和 -dp/dtmax恢复率分别为 (42 .81± 12 .56) %、(3 0 .67± 16.2 2 ) %和 (2 9.49± 10 .13 ) % ;Ⅲ组LVDP、+dp/dtmax及 -dp/dtmax恢复率分别为 (84.15± 13 .56) %、(69.49± 10 .3 6) %和 (58.3 7± 12 .45) % ,两组间有显著性差异 (P <0 .0 1)。Ⅱ组、Ⅲ组Bcl -2mRNA表达阳性细胞面积百分数分别为 (8.3± 2 .5) %、(76.3±13 .5) % ,两组间有显著性差异 (P <0 .0 1)。结论　缺血预处理可上调Bcl -2mRNA表达 ,参与未成熟心肌保护第二窗的形成 ,促进未成熟心肌缺血 /再灌注后心室功能恢复     

应用门控SPECT测量左心室功能的方法学研究

目的：试用门控心肌显像测定左室功能并与心血池显像结果比较。材料和方法：61例受检者进行了Tc-99m—MIBI门控心肌显像及心血池显像．结果：门控断层心肌显像的短轴中间部左室功能结果与平衡法心血池显像有良好的相关性(r=0．82）。结论：门控心肌断层显像测定的左室功能结果方法简便可靠．能同时反映心肌直流及左室功能。     

The pathology of cardiac ischaemia: Cellular and molecular aspects

This study evaluates the morphological and phenotypic changes that occur in squamous cell carcinoma of the head and neck when local infusions of interleukin-2 (IL-2) are given. Twelve patients were treated with a range of doses of IL-2 (3 × 10³ to 3 × 10⁶ international units/day) by continuous intra-arterial infusion for 10 days. Biopsies of the tumour were taken pre- and 48 h post-therapy, snap-frozen, cut, and examined histologically and immunocytochemically. Local infusions of IL-2 increase the numbers of antigen-presenting Langerhans cells (CDIa-positive) and infiltrating lymphocytes, predominantly of the CD3 and CD4 (T-helper) phenotypes. Locally infused IL-2 results in the expression of MHC (major histocompatibility complex) class II antigens on the surface of the tumour cells, capillary and post-capillary endothelial cells, and peri-tumoural macrophages. Intratumoural NK (natural killer) cells and CD8-positive (T-cytotoxic) infiltrating lymphocytes were not increased by this therapy and CD25 (IL-2 receptor) was only increased in those patients treated at the lower does levels. The system of intra-arterial cytokine infusion into head and neck tumours developed in this study is a useful model to examine the biological effects of cytokines, since in vivo they are mainly produced and act locally, Furthermore, the infused tumours are easily accessible to biopsy. The results from studies such as this may influence the design of tumour-targeted cytokine gene therapy programmes.     

碘杂环化合物对离体豚鼠心乳头肌动作电位和收缩力的作用

采用细胞内微电极记录技术,同步观察了3,6-[二甲氨基]-二苯并碘因甲酸盐(IHC-64)对豚鼠心乳头肌细胞动作电位和收缩力的作用。50μmol/L IHC-64抑制心肌收缩力,而不影响快反应动作电位。增加IHC-64浓度,动作电位0相最大峰值(APA)、除极速率(dp/dt_(max))和复极50％和90％时程(APD_(50)、APD_(90))被明显抑制。IHC-64抑制慢反应动作电位,提高细胞外钙浓度可拮抗这种抑制。结果提示,IHC-64主要抑制慢Ca~(2+)内流,同时也部分抑制快Na~+内流,它可能是一种新型B类钙通道阻滞剂。     

1,6-二磷酸果糖治疗新生儿缺氧缺血性脑病合并心肌损害疗效观察

目的探讨1,6-二磷酸果糖(FDP)治疗新生儿缺氧缺血性脑病(HIE)合并心肌损伤的疗效.方法随机分成治疗组和对照组,均给予常规治疗,治疗组加用FDP 0.25～0.4g/(kg·次),1 次d静滴,10 d为一疗程,治疗前后均进行心肌酶测定.结果治疗组临床症状改善及心肌酶恢复效果均优于对照组,两组差异有显著性(P＜0.05).结论 FDP对HIE时的脑损伤及心肌损伤均有良好效果.     

Antagonism of novel inotropic agents at A1 adenosine receptors and m-cholinoceptors in human myocardium

Summary The effects of the new inotropic agents saterinone, sulmazole, UD-CG 212.C1 and milrinone at A₁ adenosine receptors and m-cholinoceptors were evaluated in human myocardium from patients with heart failure. At A₁ adenosine receptors, all compounds inhibited ³H-DPCPX-binding to ventricular membrane preparations at micromolar concentrations. As judged from the K_i-values, the rank order of potency was saterinone > sulmazole > UD-CG 212.C1 > milrinone. The new inotropic agents also displaced the binding of ³H-QNB at m-cholinoceptors. Except for saterinone, the concentration ranges of mean K_i-values were considerably higher at m-cholinoceptors than at A₁ adenosine receptors. The rank order of potency was saterinone > sulmazole > UD-CG 212.Cl > milrinone. Competition of the A₁ adenosine receptor agonist R-PIA to ³H-DPCPX-binding showed a biphasic curve with a shallow slope (Hill coefficient n_H = 0.63) and revealed two affinity states of the A₁ adenosine receptor. In the presence of guanine nucleotides [Gpp(NH)p], the competition curve showed one low affinity class of binding sites and was shifted to the right. In contrast, the competition curves of the new inotropic agents were characterized by a monophasic, steeper slope (mean Hill coefficient n_H = 0.98). Guanine nucleotides had no effect. Similar results were obtained with saterinone and carbachol at m-cholinoceptors. Competition with carbachol revealed three affinity states of the m-cholinoceptor, the superhigh affinity binding was reversed by Gpp(NH)p. Competition with saterinone revealed one class of binding sites which was not influenced by Gpp(NH)p. Accordingly, in isolated, electrically driven human atrial trabeculae, the negative inotropic effect of adenosine was antagonized concentration-dependently by saterinone, sulmazole and UD-CG 212.Cl. Similarly the negative inotropic effect of carbachol was antagonized concentration-dependently by saterinone. It is concluded that the new inotropic agents bind to A₁ adenosine receptors and that their interaction is of antagonist nature. This mechanism might contribute to their capacity to enhance force of contraction by stimulation of cAMP-formation in addition to phosphodiesterase inhibition. The effects of saterinone may be partially due to antagonism at m-cholinoceptors. This is presumably not the case with the other inotropic agents studied given their low affinity for this receptor.Send offprint requests to M. Böhm at the above addressSupported by the Deutsche Forschungsgemeinschaft