Effects of sevoflurane on myocardial metabolism during postischemic reperfusion in the rat

In experiments on isolated rat heart lung preparation, the effects of sevoflurane on myocardial metabolism during postischemic reperfusion were evaluated with intramyocardial high energy phosphates, lactate and glycogen. Hearts were perfused for 10min initially and made globally ischemic for 8min. Afterwards, they were reperfused for 12min. Sevoflurane was administered from 5min after the start of perfusion to the end of reperfusion. There was no significant difference in myocardial lactate levels between the sevoflurane (S) and control groups. However, the myocardial ATP level in Group S was significantly higher than that in control (17.45 ± 1.51 vs 15.50 ± 0.87:P < 0.01). The administration of sevoflurane to the isolated rat heart during pre- and post-ischemia enhanced metabolic recovery in the postischemic state.(Kashimoto S, Oguchi T, Kume M et al.: Effects of sevoflurane on myocardial metabolism during postischemic reperfusion in the rat. J Anesth 2: 23–26, 1989)     

异丙酚和硫喷妥钠对离体缺血后心脏左室功能的影响

目的 在离体灌注兔心比较了异丙酚和硫喷妥铵对缺血后心脏左室收缩、舒张功能作用的差异。方法 分别在非缺血心脏和缺血２０分再灌注１５分心脏给予异丙酚（２０μｍｏｌ／Ｌ、５０μｍｏｌ／Ｌ）或硫喷妥钠（２００μｍｏｌ／Ｌ、５００μｍｏｌ／Ｌ）,观察左室收缩功能（ＬＶ＋ｄｐ／ｄｔｍａｘ、ＬＶＤＰ）、舒张功能（ＬＶ－ｄｐ／ｄｔ ｍａｘ、ＬＶＤＥＰ）及灌出液出ＬＤＨ、ＣＰＫ活性的变化。结果 ２０μｍｏｌ／Ｌ异丙     

Amrinone improves postischemic myocardial metabolism in the rat heart-lung preparation

Amrinone, a phosphodiesterase inhibitor, is a non-glycosidic noncatecholamine with both vasodilator and positive inotropic effects. We were interested in assessing the effect of amrinone on postischemic cardiac performance in the isolated heart-lung preparation. Twenty-four male Wistar-ST rats were used. They were randomly divided into three groups. Amrinone, 10 μg·ml⁻¹ or 100 μg·ml⁻¹ was administered 8 min after the start of perfusion except in the control group. Ten minutes after the start of perfusion, all hearts were made globally ischemic for 8 min. Subsequently, the preparations were reperfused for 10 min. At the end of the experimental period, the hearts were freeze-clamped, and then myocardial high-energy phosphates, lactate, pyruvate, and glycogen were measured. Hemodynamic parameters in all groups decreased significantly during ischemia. However, there were no significant differences among the groups. The myocardial ATP level in the 100 μg·ml⁻¹ group was significantly higher than that in the control group. Adenosine diphosphate (ADP) and adenosine monophosphate (AMP) levels in the 100 μg·ml⁻¹ group were significantly lower than those in the control group. Myocardial lactate, pyruvate, and glycogen levels were not significantly different among the groups. This result suggests that amrinone improves postischemic myocardial metabolism. Although we could not measure coronary flow, amrinone might increase coronary flow with direct coronary vasodilation which would have increased the myocardial ATP and energy charge levels.     

Biochemical and histological investigation of famotidine effect on postischemic reperfusion injury in the rat ovary

Background/Purpose

In this study, an investigation was performed on the ovarian tissue of rats subjected to ischemia-reperfusion for the effect of famotidine on certain parameters of oxidation-antioxidation, cell DNA damage, and histological appearance.

Methods

The effects of famotidine on certain parameters of oxidation-antioxidation (total glutathione [tGSH], superoxide dismutase [SOD], malondialdehyde) and cellular DNA injury in the ovarian tissue of rats subjected to ischemia-reperfusion were investigated and underwent histological examination.

Results

The results show levels of 5.2 ± 0.6 nmol/g protein for tGSH, 8.3 ± 0.8 U/g for SOD activity, and 7.7 ± 0.9 μmol/g protein for malondialdehyde (P < .0001 when compared with controls) in ovarian tissue subjected to ischemia-reperfusion following famotidine treatment. The tGSH levels in control rats and in a healthy animal group were, respectively, 1.76 ± 0.7 and 5.5 ± 0.3 nmol/g protein (P < .0001). The SOD activity was 3.2 ± 0.9 U/g in control and 9.2 ± 0.6 U/g in healthy animal tissues. The differences between the values in the treatment and the control group, and between the healthy animal group and the control group were both highly significant (P < .0001). It was also observed that famotidine prevented, to a significant extent, an increase in the level of 8-hydroxy-2-deoxyguanine/guanine, a DNA damage product, as compared with the control group.

Conclusion

These biochemical and histological results show that famotidine protects the ovarian tissue from ischemia-reperfusion injury.     

异丙酚、硫喷妥钠对大鼠心肌细胞钙、钾通道电流的影响

目的 研究异丙酚、硫喷妥钠对大鼠心肌细胞钙、钾通道电流的影响。方法 急性分离大鼠心室肌细胞,采用全细胞膜片钳技术,观察不同浓度异丙酚、硫喷妥钠对大鼠心肌细胞L型钙通道电流(I_(Ca))、延迟整流钾通道电流(IK)的作用。结果 随浓度增加,异丙酚和硫喷妥钠对I_(Ca)的抑制作用逐渐增强,与浓度呈正相关,相关系数分别为0.98、0.97(P<0.01),异丙酚、硫喷妥钠的IC_(50)分别为138.8±9.5、102.4±2.0μmol·L~(-1)。50μmol·L~(-1)异丙酚、100μmol·L~(-1)硫喷妥钠并不影响钙通道激活曲线的形态,但使钙通道稳态失活曲线向超极化方向分别移动3、7mV(P<0.05)。50μmol·L~(-1)异丙酚、100μmol·L~(-1)硫喷妥钠使IK降低10％和24％(P<0.01),250μmol·L~(-1)异丙酚、500μmol·L~1硫喷妥钠使IK进一步降低,较基础值下降了18％和46％(P<0.01)。结论 异丙酚、硫喷妥钠呈浓度依赖地抑制大鼠心肌细胞L型I_(Ca),其抑制作用主要与加快钙通道的失活有关,两药对IK也有抑制作用。     

异丙酚和硫喷妥钠对心肌内游离Ca2+浓度的影响

目的　观察异丙酚和硫喷妥钠对心肌细胞内游离Ｃａ２＋ 浓度的影响,以探讨静脉麻醉药对心肌细胞内游离Ｃａ２＋ 的作用及其机制。方法　心肌细胞分离培养７～９ 天,以Ｆｕｒａ２／ＡＭ 荧光指示剂负载后,实验组Ａ 加入实验用药孵育１０ 分钟进行Ｃａ２＋ 测定;实验组Ｂ：加入实验用药１０ 分钟后,加ＫＣｌ４０ｍ ｍ ｏｌ／Ｌ,１ 分钟后进行Ｃａ２＋ 测定。结果　临床剂量的异丙酚和硫喷妥钠对静息心肌细胞内Ｃａ２＋ 浓度无明显影响,超临床剂量的异丙酚和硫喷妥钠使静息细胞内Ｃａ２＋ 明显降低。４０ｍ ｍ ｏｌ／Ｌ的ＫＣｌ可使心肌细胞内Ｃａ２＋ 浓度明显升高,异丙酚和硫喷妥钠对高浓度ＫＣｌ所激发Ｃａ２＋ 内流均有明显的抑制,并呈剂量依赖性。结论　异丙酚和硫喷妥钠降低心肌细胞内钙离子浓度。他们在完整心肌的负性肌力作用可能与其部分抑制兴奋收缩耦联过程中钙离子内流和抑制静息状态下的钙溢流有关     

丙泊酚和硫喷妥钠对大鼠心肌细胞钾通道电流的影响

目的 观察丙泊酚和硫喷妥钠对大鼠心肌细胞延迟整流钾电流和内向整流钾电流的影响,探讨这两种静脉全麻药对心脏功能的影响与两种不同通道电流的关系。方法 急性分离大鼠心室肌细胞,采用全细胞膜片钳技术,观察丙泊酚和硫喷妥钠对大鼠心肌细胞钾通道电流的影响。结果 诱导峰浓度的丙泊酚(50μmol/L)、硫喷妥钠(100μmol/L)使延迟整流钾电流降低10.3％和24.4％(P<0.01)。5倍诱导峰浓度的丙泊酚和硫喷妥钠使延迟整流钾电流进一步降低,较基础值下降了17.9％和45.7％(P<0.01)。1和5倍诱导峰浓度的硫喷妥钠使内向整流钾电流较基础值下降了43.8％和66.5％(P<0.01),但两种浓度的丙泊酚并不影响内向整流钾电流的幅度。结论 丙泊酸和硫喷妥钠呈浓度依赖地抑制延迟整流钾电流,可部分拮抗对钙电流的抑制作用。硫喷妥钠对内向整流钾电流有明显抑制作用,可能与其易化肾上腺素的致心律失常作用有关。两药对细胞表面不同离子通道的作用具有选择性。     

异丙酚和硫喷妥钠对颅脑手术患者脑血流的影响

应用经颅超声多普勒（ＴＣＤ）监测仪观察异丙酚、硫喷妥钠对颅脑手术患者大脑中动脉血流速度的影响。选择２２例择期手术患者，ＡＳＡＩ～ Ⅱ级，年龄 ２０～５８岁，随机分为二组：异丙酚组（２. ０ｍｇ／ｋｇ，ｎ＝１２例）和硫喷妥钠组（４ｍｇ／ｋｇ，ｎ＝１０例）。监测指标包括大脑中动脉血流速度（ＣＢＦＶ）、心率（ＨＲ）、平均动脉压（ＭＡＰ）和呼气末ＣＯ２分压。测定程序为给药前５分钟和给药后ＩＱ分钟，通过控制呼吸维持ＰｅｔＣＯ２相对恒定。结果表明，异丙酚组ＭＡＰ、搏动指数，峰值和平均大脑中动脉血流速度分别下降１３％、２９％、３１％和２０％，而硫喷妥钠组则分别下降９．７％、１４％、２２％和１３％。除给药后血管阻力指数异丙酚组明显低于硫喷妥钠组外，其余各指标两组间无显著差异。异而酚对脑循环的影响和硫喷妥钠相似，对颅脑手术患者麻醉诱导是有益的。     

异丙酚、咪唑安定和硫喷妥钠对鼠局灶脑缺血/再灌注后氨基酸堆积的影响

目的观察异丙酚、咪唑安定和硫喷妥钠对鼠局灶脑缺血/再灌注后缺血部位氨基酸类神经递质含量的影响.方法采用大脑中动脉(MCA)内线栓法诱发局灶脑缺血.雄性SD大鼠随机分为5组,每组6～7只.缺血组仅经历3 h MCA阻塞;再灌注组经历3 h MCA阻塞和3 h再灌注;三个用药组于再灌注前即刻分别腹腔内注射异丙酚、咪唑安定和硫喷妥钠50 mg@kg-1,再灌注3h后,处死鼠,迅速取脑,用高效液相色谱法测脑组织兴奋性氨基酸类含量.结果异丙酚、咪唑安定明显减少再灌注期缺血部位门冬氨酸、谷氨酸堆积;异丙酚增强,而咪唑安定减小GABA堆积;硫喷妥钠无明显作用.结论异丙酚和咪唑安定可能通过加快再灌注期兴奋性氨基酸的清除而产生脑保护效应.     

四种常用静脉麻醉药对老年病人血液动力学影响的比较

目的 探讨脑电双频指数(BIS)为50时，硫喷妥钠、丙泊酚、咪唑安定、依托咪酯用于老年病人全麻诱导的剂量及其对血液动力学的影响。方法 65岁以上的老年病人48例，随机分为四组：硫喷妥钠组，丙泊酚组，咪唑安定组，依托咪酯组。四组均缓慢静注，并且用HXD-1型脑电监测仪测量每例病人的BIS。当BIS逐渐下降至50时停止静注，分别于注药前、注药后1、3、5、10min用Rheo Cardio Monitor连续非创伤性血液动力监测仪记录和计算出血液动力学有关参数。结果 BP下降以丙泊酚组为显著。丙泊酚组和硫喷妥钠组的PEP/LVEF比值明显增加，但丙泊酚组＞硫喷妥钠组。除依托咪酯组以外其他各组的每搏指数(SD、心脏指数(CI)、射血速率(EV)和每搏功(LVP)均有不同程度的降低，但以丙泊酚组为显著。依托咪酯组体循环血管阻力(SVR)无明显变化，硫喷妥钠组和咪唑安定组均有不同程度的升高，以咪唑安定组为显著，丙泊酚组明显下降。舒张末容量(EDV)咪唑安定组明显下降，其他各组无明显变化。结论 四种静脉麻醉药对老年病人血液动力学的影响由大到小依次为丙泊酚＞咪唑安定＞硫喷妥钠＞依托咪酯。BIS为50时，老年病人各静脉麻醉药的等效剂量为硫喷妥钠4mg／kg、丙泊酚1．2mg／kg、咪唑安定0．16mg／kg、依托咪酯0．34mg／kg。对于心功能较差和血容量不足的老年病人全麻诱导，依托咪酯是首选的静脉麻醉诱导药。     

Effects of propofol and thiopental on the central nervous system during nociceptive stimulation in cats

Purpose. Nociceptive stimulation may increase central nervous system (CNS) activity during anesthesia. However, it is not known whether propofol and thiopental have a similar inhibitory effect on the CNS during nociceptive stimulation. Therefore, we compared the antinociceptive effects of propofol and thiopental in cats. Methods. In 12 cats, anesthesia was induced with 4% halothane in oxygen and maintained with 0.5% halothane in oxygen. The cortical electroencephalogram (EEG) and the electrical activity from the midbrain reticular neurons (R-MUA) were measured before and after sciatic nerve stimulation. The cats were then allocated to receive cumulative doses of either propofol (n = 6) or thiopental (n = 6) i.v. at 5-min intervals. Two minutes after each dose, the cortical EEG and the R-MUA were compared before and after sciatic nerve stimulation. Results. Propofol and thiopental depressed the basal R-MUA to a similar degree at each dose. Sciatic nerve stimulation increased the R-MUA, and there were no differences in the maximum R-MUA values between propofol and thiopental. The cortical EEGs after each dose of anesthetic without stimulation showed similar patterns, and the patterns of change with stimulation were also similar for these two anesthetics. Conclusion. Propofol and thiopental have similar antinociceptive effects in cats. Received: October 10, 2000 / Accepted: April 2, 2001     

异丙酚及咪唑安定和硫喷妥钠对鼠局灶脑缺血/再灌注损伤的影响

目的 观察异丙酚、咪唑安定和硫喷妥钠对鼠局灶脑缺血／再灌注后的神经功能和病理结果的影响。方法 雄性SD大鼠,采用可逆性大脑中动脉内线栓法诱发局灶脑缺血。缺血3h,再灌注24h后,作神经功能缺陷评估,然后取脑,TTC染色,用Image软件系统作图像分析,计算脑梗塞和脑水肿容积,电镜下观察梗塞边缘组织的细胞超微结构。动物分五组：缺血组、再灌注组、用药组（异丙酚、咪唑定安和硫喷妥钠）结果 异丙酚和咪唑安定明显改善鼠神经功能缺陷程度,降低脑梗塞和脑水肿容积,并减少梗塞边缘组织细胞死亡。异丙酚的脑保护效应强于咪唑安定。结论 异丙酚和咪唑安定有拮抗鼠局灶脑缺血／再灌注损伤的作用。     

Age-dependent changes of postischemic reperfusion in rat skin

Ischemia-reperfusion plays a certain role in causing skin damage associated with pressure sores. In this study, changes in cutaneous hemodynamics during reperfusion were investigated in young and older rats. After cessation of 1-hour or 2-hour ischemia, the skin blood flow increased transiently (postischemic hyperemia) and quickly returned to the baseline in young and older rats. After 4-hour ischemia, however, the postischemic hyperemia was reduced in both groups, and the skin blood flow decreased below the baseline for a few hours in older rats. The skin blood flow tolerated well the repeated exposures to 1-hour ischemia in both groups. In 2-hour ischemia experiments, the postischemic hyperemia was preserved after the second ischemic period in young rats but not in older rats. These results suggest that the tolerance of skin microcirculation to ischemia-reperfusion may decrease with increasing age.     

硫喷妥钠麻醉对小鼠T淋巴细胞亚群的影响

目的 观察静脉麻醉药硫喷妥钠对小鼠T淋巴细胞亚群的影响。方法 T淋巴细胞亚群的测定应用单克隆抗体直接免疫荧光技术由流式细胞仪测定。结果 硫喷妥钠麻醉后20小时小鼠外周血中CD4T淋巴细胞、CD4／CD8比值均显著下降。同时测定血中白细胞总数，实验组与对照组比较统计学差异无显著意义。结论 硫喷妥钠麻醉引起小鼠细胞免疫功能抑制。     

缺血预处理对兔骨骼肌再灌注损伤延迟保护作用的实验研究

目的探讨缺血预处理对兔骨骼肌再灌注损伤是否存在早期、延迟保护作用及保护程度。方法选择30只新西兰大白兔随机等分为对照组、早期保护组(EP)和延迟保护组(DP)。对照组直接用气囊止血带阻断兔后肢血流4h,造成骨骼肌缺血再灌注损伤模型。EP和DP组先进行缺血预处理,分别在预处理后立即和24h后用气囊止血带阻断兔后肢血流4h造成缺血再灌注模型。测定再灌注期血清中肌酸磷酸激酶(CPK)、天门冬酰胺氨基转移酶(AST)和超氧化物歧化酶(SOD)含量,光、电镜下观察骨骼肌结构变化。结果再灌注后1、2、4、8h,EP与DP组血清中CPK和AST的含量均明显低于对照组(P<0.01);SOD含量明显高于对照组(P<0.01),而EP与DP组之间差异无显著性意义(P>0.05)。骨骼肌线粒体空泡变性和肌原纤维溶解均延迟出现,其病变程度明显轻于对照组。结论缺血预处理不仅存在早期、延迟保护作用,且均能提高骨骼肌对长时间缺血的耐受能力,减轻骨骼肌缺血再灌注损伤程度,这两种保护作用的程度无明显差异。     

Effects of pulsatile reperfusion on postischemic recovery of myocardial function after global hypothermic cardiac arrest

It has been postulated that pulsatile blood flow helps to preserve the myocardium after ischemia. However, its effect on postischemic myocardium during cardiopulmonary bypass has not been clearly defined. To determine if pulsatile reperfusion improves postischemic recovery of cardiac metabolism and performance, we subjected 20 dogs to 60 minutes of aortic cross-clamping followed by 45 minutes of pulsatile (P group; 10 dogs) or nonpulsatile (NP group; 10 dogs) reperfusion. Left ventricular function was measured at a controlled preload in both groups before induction of global ischemia and after termination of bypass. Segmental length (assessed by sonomicrometry) was used to determine dimensional changes. Ventricular pressures were measured with solid-state micromanometers. Percent recovery of left ventricular peak systolic pressure, its first derivative, and stroke work were 66%, 59%, and 38%, respectively in the NP group and 82%, 76%, and 65% in the P group. The postarrest decrease in segmental shortening was minimized in the P group; left ventricular function curves and the slope of the end-systolic pressure-length relationship also indicated better performance after pulsatile reperfusion than after nonpulsatile reperfusion. Myocardial lactate extraction was transiently improved during the early pulsatile reperfusion period. We conclude that pulsatile reperfusion provides better myocardial preservation than nonpulsatile perfusion after 60 minutes of induced global ischemia.     

异丙酚、硫喷妥钠对大鼠脑局灶性缺血/再灌注损伤对血脑屏障通透性改变的影响

目的 比较异丙酚和硫喷妥钠对大脑局灶性缺血／再灌注损伤中血脑屏障（ＢＢＢ）通 性变化及神经病理学的影响。方法 ６０只成年大鼠随机分为５组,均采用尼龙线栓堵左侧大脑中动脉的方法建立暂时性局灶性脑缺血模型：对照组（ＭＣ组）不用全麻药;异丙酚预防组（ＭＰ１组）及硫喷妥钠预防组（ＭＴ１组）,在制作大脑中动脉闭塞模型前３０ｍｉｎ分别静脉注射异丙酚２０ｍｇ／ｋｇ或２．５％硫喷妥钠溶液４０ｍｇ／ｋｇ,继之以异丙     

Improved energy preservation following gentle reperfusion after hypothermic, ischemic cardioplegia in infarcted rat hearts

The influence of temperature and pressure during early reperfusion after 2 h of hypothermic, cardioplegic ischemia was investigated. Adenosine triphosphate (ATP) and creatinephosphate (CP) were measured after 45-min reperfusion. The experiments were carried out in normal and previously infarcted rat hearts (the left coronary artery having been ligated 3 weeks carlier). Four groups, each containing six hearts, were studied. Group 1 consisted of normal hearts reperfused with an abrupt rise in temperature and pressure, group 2 of normal hearts exposed to slowly rising temperature and pressure, and group 3 and 4 of previously infarcted hearts. Reperfusion procedures in groups 3 and 4 were the same as in group 1 and 2, respectively. The study showed that previously infarcted hearts have a lowered tolerance to ischemia and that the reperfusion technique may influence the preservation of myocardial energetics, although this influence was not statistically significant in normal hearts following only 2 h of ischemia. The gently reperfused infarcted hearts had energy stores equal to the normal hearts after 2 h of ischemia and 45 min of reperfusion, whereas the infarcted hearts reperfused in a rougher mode had significantly lowered values (P<0.05 for ATP and P<0.01 for CP).     

硝普钠对心脏瓣膜置换术后早期氧代谢的影响

目的　观察硝普钠对心脏瓣膜置换术后早期氧供需平衡的影响。方法　 2 4例心脏瓣膜置换术病人随机分为硝普钠组 (A组 )和对照组 (B组 ) ,每组 12例。A组病人在心肺转流 (CPB)复温时用硝普钠 1 0 μg·kg 1·min 1输注。停CPB后改为 0 8～ 4 6 μg·kg 1·min 1输注。观察两组病人氧供、氧耗、氧摄取率、混合静脉血氧饱和度、动脉血乳酸和心指数的变化。结果　停CPB后两组病人氧供 ,心指数同时点值比较无显著差异 (P >0 0 5 ) ;停CPB后 1、2h时A组病人氧耗、氧摄取率明显高于B组病人同时点值 (P <0 0 5 ) ,动脉血乳酸明显低于B组病人 (P <0 0 5 ) ,且A组病人呈病理性氧供依赖持续时间短于B组病人。结论　硝普钠与正性肌力药物合用可明显改善心脏瓣膜置换术早期氧代谢障碍     

硫喷妥钠对内毒素诱导小鼠肺组织NF-κB表达的影响

目的研究硫喷妥钠对内毒素（LPS）诱导小鼠肺组织NF-κB的表达的影响。方法雄性昆明小鼠24只，随机分为4组（n=6）：对照组（C组）、LPS组（L组）、硫喷妥钠处理组（L＋T组）、单纯硫喷妥钠处理组（T组）。C组腹腔注射生理盐水1ml／ks；L组腹腔注射LPS5mg／kg；L＋T组腹腔注射LPS5mg／kg 20min时再注射1％硫喷妥钠注射液60mg/kg；T组单纯腹腔注射1％硫喷妥钠注射液60mg／kg。在注射LPS后3h放血处死小鼠，立即开胸取肺。免疫蛋白印迹法测定肺组织NF-κB p65的表达；酶联免疫吸附法测定肺组织肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）含量。结果与C组相比，L、L＋T组肺组织NF-κB p65表达增加，L、L＋T、T组肺组织，TNF-α、IL-1β含量上升（P〈0．05）；与L组相比，L＋T、T组肺组织NF-κB p65表达降低，肺组织TNF-α，IL-1β含量降低（P〈0．05）。结论硫喷妥钠通过下调小鼠LPS诱导的肺组织NF．KB065表达，降低了TNF-α及IL-1β的释放。