降钙素基因相关肽介导缺血预适应对溶血性磷脂酰胆碱损伤心肌的保护作用

研究心脏缺血预适应(PC)对溶血性磷脂酰胆碱(LPC)损伤心肌作用的影响，并探讨降钙素基因相关肽(CGRP)在PC中的作用. 离体大鼠心脏Langendorff法灌流，记录心率，冠脉流量，左室压和左室压最大上升速率(+dp/dt_max)，并测定灌流液中肌酸磷酸激酶(CPK)含量. 结果显示，LPC能降低各项心功能指标，并使CPK释放增加；PC(缺血5 min， 再灌5min，重复3次)能减轻LPC的损伤作用；PC的心肌保护作用可被选择性CGRP受体拮抗剂CGRP_8-37所取消；预先给予CGRP或辣椒素能产生与PC相同的心肌保护作用. 对照组, LPC, PC+LPC, CGRP_8-37, CGRP_8-37+PC+LPC, CGRP+LPC, CGRP_8-37+CGRP+LPC, 辣椒素+LPC组CPK释放量分别为0.26±0.05, 2.30±0.22, 0.25±0.03, 0.30±0.08, 2.60±0.15, 0.24±0.05, 2.70±0.20和0.25±0.07 μmol·min^-1·g^-1湿组织. 这些结果提示：1) PC对LPC所致心肌损伤具有保护作用；2) PC的保护作用是由CGRP所介导；3) CGRP或辣椒素可模拟PC的保护作用.     

Mediation of calcitonin gene-related peptide in protection of ischemic preconditioning in rat hindlimbs

目的：研究降钙素基因相关肽（ＣＧＲＰ）介导缺血预适应对血管内皮的保护．方法：大鼠后肢缺血２ｈ后，观察乙酰胆碱诱导血管内皮依赖性舒张反应．结果：缺血不影响去甲肾上腺素的缩血管效应，但能显著削弱乙酰胆碱的舒血管效应．缺血预适应能阻止长时间缺血对乙酰胆碱舒血管效应的抑制作用，这种保护作用可被反复应用辣椒素耗竭ＣＧＲＰ所取消．急性应用辣椒素促进ＣＧＲＰ释放或外源性应用ＣＧＲＰ均可产生预适应样的保护作用．结论：大鼠后肢缺血预适应对内皮细胞的保护与辣椒素敏感的感觉神经有关；ＣＧＲＰ能模拟缺血预适应保护血管．     

Effect of calcitonin gene-related peptide-induced preconditioning on attenuated endothelium-dependent vasorelaxation induced by lysophosphatidylcholine

目的：研究降钙素基因相关肽（ＣＧＲＰ）诱导预适应对溶血磷脂酰胆碱（Ｌｙｓ）抑制内皮依赖性舒张的作用．方法：用苯福林收缩兔与大鼠离体胸主动脉环，观察Ｌｙｓ对乙酰胆碱（ＡＣｈ）所致内皮依赖性舒张的影响．结果：ＣＧＲＰ预处理兔和大鼠离体胸主动脉环显著减轻Ｌｙｓ对ＡＣｈ舒血管效应的抑制，其作用可被蛋白激酶Ｃ（ＰＫＣ）抑制剂Ｈ７所取消．结论：ＣＧＲＰ诱导预适应对所致内皮细胞损伤具有拮抗作用，此作用与激活ＰＫＣ有关．     

Protection of ischemic preconditioning mediated by endogenous opioid peptides in rat hindquarters

研究了内源性阿片肽介导大鼠后肢缺血预适应的保护作用．后肢缺血２ｈ，乙酰胆碱（ＡＣｈ）诱导的血管内皮依赖性舒张性反应明显下降．缺血预适应（缺血５ｍｉｎ，再灌５ｍｉｎ，重复３次）能显著减弱长时间缺血对ＡＣｈ舒血管效应的抑制作用，这种保护作用可被纳洛酮（３ｍｇ·ｋｇ－１）取消．预先给予吗啡（３００μｇ·ｋｇ－１）也能产生与缺血预适应相同的血管内皮保护作用．然而，预先用辣椒素（５０ｍｇ·ｋｇ－１）耗竭降钙素基因相关肽后，吗啡的保护作用被取消．结果提示，内源性阿片肽介导大鼠后肢缺血预适应的血管保护作用，其机理可能涉及内源性降钙素基因相关肽．     

Attenuation of myocardial injury due to oxygen free radicals(OFR) by pretreatment with OFR or calcitonin gene-related peptide

目的：研究氧自由基（ＯＦＲ）及降钙素基因相关肽（ＣＧＲＰ）预处置对ＯＦＲ所致离体大鼠心脏损伤的拮抗作用．方法：Ｌａｎｇｅｎｄｏｒｆ法灌流心脏，电解ＫＨ液产生ＯＦＲ．结果：ＣＧＲＰ或ＯＦＲ预处置减轻ＯＦＲ所致心脏收缩功能下降，冠脉流量减少和肌酸激酶（ＣＫ）释放增加．蛋白激酶Ｃ（ＰＫＣ）抑制剂Ｈ７可取消ＯＦＲ预处置的心脏保护作用（对照组，ＯＦＲ损伤组，ＯＦＲ预处置组，Ｈ７加ＯＦＲ预处置组及Ｈ７组的ＣＫ释放量分别是１１０±７，２１５±２３，１６９±１４，２４０±３０，１１３±１９Ｕ·Ｌ－１）．结论：ＯＦＲ或ＣＧＲＰ预处置对ＯＦＲ所致心肌损伤具有拮抗作用，该作用与ＰＫＣ激活有关．     

Protection of L－arginine against lysophosphatidy lcholine－inducedmy ocardi alinjury inisolated ratheart

在离体大鼠心脏观察了Ｌ－精氨酸对溶血性磷脂酰胆碱（ＬＰＣ）损伤心肌作用的影响．ＬＰＣ（５μｍｏｌ·Ｌ－１）引起心率减慢，冠脉流量减少，心脏功能降低（ＬＶＰ和ＬＶｄｐ／ｄｔｍａｘ下降）及肌酸激酶（ＣＰＫ）释放增加．３０μｍｏｌ·Ｌ－１Ｌ－精氨酸能促进心率恢复，增加冠脉流量和改善心脏功能，但仅ＬＶｄＰ／ｄｔｍａｘ恢复显示统计学差异；３００μｍｏｌ·Ｌ－１Ｌ－精氨酸能显著改善心脏功能，促进心率和冠脉流量的恢复，减少ＣＰＫ释放．结果提示：Ｌ－精氨酸对ＬＰＣ所致心肌损伤具有一定的保护作用．     

Relationship between calcitonin gene-related peptide and endothelium-dependent vasorelaxation in streptozotocin-induced diabetic rats

在糖尿病大鼠，检测血浆降钙素基因相关肽（ＣＧＲＰ）含量的变化，并探讨其与血管内皮舒张功能的关系．糖尿病大鼠血浆ＣＧＲＰ的含量显著低于对照组（０．２２±０．０８ｖｓ０．３７±０．１３μｇ·Ｌ－１，Ｐ＜０．０１），但丙二醛含量显著增加；糖尿病大鼠胸主动脉对乙酰胆碱诱导内皮依赖性舒张反应显著降低．结果提示：糖尿病大鼠血管内皮舒张功能的削弱与血浆ＣＧＲＰ含量的下降有关．     

Isoflurane preconditioning protects against ischemia-reperfusion injury partly by attenuating cytochrome c release from subsarcolemmal mitochondria in isolated rat hearts

AIM: To examine if isoflurane preconditioning can attenuate ischemia/reperfusion injury by reducing cytochrome c release from inner mitochondrial membrane. METHODS: Isolated hearts of Sprague-Dawley rats were perfused on Langendorff apparatus. Hearts were randomly assigned to a non-treated group (CON group, n=12) or three isoflurane preconditioning groups (0.5% ISC group, 1.0% ISC group, and 2.0% ISC group; n=12). In the latter three groups, isoflurane was given at concentrations of 0.5%, 1.0%, and 2.0% for 15 min with 15-min washout before 30-min ischemia. Subsarcolemmal mitochondria of the myocardium were isolated after 60-min reperfusion. Hemodynamics of the each heart was recorded, infarct size of the hearts and contents of cytosolic cytochrome or mitochondrial cytochrome c were measured at the end of reperfusion. Morphology of isolated mitochondria in the four groups was evaluated, respectively. RESULTS: Compared with the CON group, cytosolic cytochrome c in 0.5% ISC group, 1.0% ISC group, and 2.0% ISC group were significantly decreased along with a significant increase of mitochondrial cytochrome c. Infarct size of the hearts in the four groups were 56%+/-12%, 41%+/-12%, 32%+/-7% and 33%+/-11%, respectively. The values of the three isoflurane preconditioning groups were significantly lower than that of the CON group (P<0.05). Isoflurane exposure before ischemia can attenuate the change of morphology of mitochondria after reperfusion. The effects of 2.0% isoflurane on reducing cytochrome c release were more remarkable than 0.5% and 1.0% concentrations of isoflurane. CONCLUSION: Myocardioprotective effects of isoflurane preconditioning were associated with attenuation of cytochrome c loss from the inner membrane of subsarcolemmal mitochondria.     

缺血预适应对大鼠小肠缺血再灌注损伤的保护作用(英文)

观察预适应对大鼠小肠缺血再灌的保护作用及对内源性神经递质降钙素基因相关肽 (CGRP)释放的影响 .选用雄性 Wistar大鼠 40只 (2 75- 32 5g) ,实验分在体和离体两部分 .(1 )在体部分 :30 min的小肠缺血和 60 min的再灌流可引起小肠湿重干重比值 (WW/DW)增高 ,血中乳酸脱氢酶 (LDH)活性 ,丙二醛 (MDA)含量显著增加 .3次 8min缺血及1 0 min再灌流预适应可降低前述缺血再灌引起的WW/DW,LDH活性及 MDA含量增高 ,但各组血液中 CGRP水平未见明显变化 .(2 )离体部分 :肠系膜上动脉插管连接灌流装置 .肠系膜上静脉插管收集流出液 .小肠灌流 1 0 min后 ,反复 3次 8min阻断灌流及 1 0 min再灌流预适应模型可使流出液中的 CGRP显著增加〔(1 .30± 0 .0 8) vs(0 .68±0 .0 5) μg· L-1,P<0 .0 1〕.结果提示 :缺血预适应对小肠缺血再灌损伤具有显著保护作用 ,CGRP可能是预适应的一种内源性神经介质     

Effect of Gαq／11 protein and ATP-sensitive potassium channels on prostaglandin E1 preconditioning in rat hearts

To investigate the effect of G~11 signaling pathway and ATP-sensitive potassium channels (KAxP channels) on prostaglandin E1 (PGE0 induced early and delay-preconditioning protection in rat hearts. METHODS: Two series of experiments were performed in Wistar rat hearts. In the first series of experiment, all rats were pretreated with PGE 40 min or 23 h 20 min before the experiment. Ischemia-reperfusion injury was induced by 30 min coronaryartery occlusion followed by 90 min reperfusion. Hemodynamics, infarct size, and scores of ventricular arrhythmias were measured. The expression of G~q/H protein in the heart was measured by Western blot analysis in the second series. RESULTS: Preconditioning with PGE~ (25 lag/kg ) markedly reduced infarct size, left ventricular enddiastolic pressure, and scores of ventricular arrhythmia. The effect of PGE1 was significantly attenuated by glibenclamide (1 mg/kg, ip), a nonselective KA~ channel inhibitor. PGE~ caused a significant increase in the expression of G~/~ protein. CONCLUSION: Activations of G~/H signal pathway and Kgrp channel played significantroles in the cardioprotection of PGE~ preconditioning in rat heart and might be an important mechanism of signal transduction pathway during the PGEj preconditioning.     

降钙素基因相关肽介导的离体大鼠心脏缺血预处置

降钙素基因相关肽介导的离体大鼠心脏缺血预处置１肖洲生，李元建２，邓汉武（湖南医科大学药理教研室，长沙４１００７８，中国）关键词降钙素基因相关肽；心肌再灌注损伤；心功能试验；肌酸激酶目的：研究降钙素基因相关肽（ＣＧＲＰ）在离体大鼠心脏缺血预处置（ＰＣ）...     

降钙素基因相关肽对阿霉素心肌细胞毒性的保护作用

目的观察降钙素基因相关肽（ＣＧＲＰ）对阿霉素所致心肌细胞毒性作用的影响。方法采用原代培养乳鼠心肌细胞，以１０－６ｍｏｌＬ－１阿霉素造成急性心肌细胞毒性模型，ＣＧＲＰ作用浓度为１０－８ｍｏｌＬ－１。测定培养基中ＬＤＨ活性及心肌细胞内丙二醛（ＭＤＡ）、钙含量。透射电镜观察心肌细胞超微结构改变。结果阿霉素引起心肌细胞ＬＤＨ漏出明显增加；细胞内ＭＤＡ、钙含量水平明显升高；心肌细胞线粒体明显肿胀、嵴排列不整齐、断裂或消失，肌浆网明显扩张，染色质凝集。阿霉素所致心肌细胞ＬＤＨ漏出与细胞内ＭＤＡ含量水平呈正相关。ＣＧＲＰ可明显减轻阿霉素所致心肌细胞ＬＤＨ漏出及细胞内ＭＤＡ、钙的蓄积，明显减轻心肌细胞超微结构的改变。结论ＣＧＲＰ通过抑制脂质过氧化反应和减轻细胞内钙超载对阿霉素心肌细胞毒性具有保护作用     

CGRP、K_(ATP)通道和脊神经在鞘内注射吗啡预处理减轻大鼠心肌缺血后损伤中的作用

目的探讨降钙素基因相关肽(CGRP)、ATP敏感性钾离子通道(KATP通道)和脊神经在鞘内注射吗啡预处理对在体大鼠心肌缺血/再灌注损伤中的保护作用。方法♂SD大鼠60只,建立鞘内置管和心肌缺血/再灌注损伤模型,随机分为10组,每组6只:对照组(CON,生理盐水)、二甲亚砜组(DMSO,GLI的溶剂)、CGRP8-37组(CGRP受体阻滞剂,3nmol.kg-1)、格列苯脲组(GLI,KATP通道阻滞剂,0.3 mg.kg-1)、利多卡因组(LID,1%盐酸利多卡因10μl)、鞘内注射吗啡预处理组(MPC,3×1μg.kg-1)、CGRP8-37+MPC组、GLI+MPC组、LID+MPC组、GLI+LID组。观察指标包括:平均动脉压(MAP)、心率(HR),计算平均动脉压和心率乘积(RPP);心肌缺血危险区(AAR)、梗死区(IS)的体积、心肌梗死面积以IS/AAR表示。结果与CON组比较,MPC组、LID组、LID+MPC组和GLI+LID组的IS和IS/AAR均明显下降(P<0.05,P<0.01);与MPC组比较,CGRP8-37+MPC组、GLI+MPC组和LID+MPC组的IS和IS/AAR均明显增加(P<0.01)。结论外周CGRP的释放、KATP通道和脊神经可能参与了鞘内注射吗啡预处理减轻大鼠心肌缺血后损伤的作用。     

中枢吗啡预处理对心脏缺血后大鼠海马CaM、血浆CGRP以及下丘脑室旁核和心肌P物质表达的影响

目的探讨侧脑室内注射吗啡预处理对在体大鼠心肌缺血/再灌注损伤的影响及可能的信号机制。方法建立模型大鼠,随机分为两个部分:①分为4组,每组6只:对照组(CON组),在缺血/再灌注前30 min内,侧脑室内微量泵注射0.9%生理盐水5 min,停止注射5 min,重复3次;预处理组(MPC组),在缺血/再灌注前30 min内,侧脑室内注射吗啡(1μg.kg-1)5 min,停止5 min,重复3次;钙调蛋白抑制剂三氟拉嗪(trifluoperazine,TFP)+预处理组(TFP+MPC组),在吗啡预处理前10 min一次侧脑室内给予TFP(浓度为20 g.L-1)5μl;另设TFP自身对照组(TFP组)。②分为3组,每组6只:假手术组(Sham组),CON组和MPC组均同第一部分。观察指标包括:平均动脉压(MAP)、心率(HR),计算平均动脉压和心率乘积(RPP);心肌缺血危险区(AAR)、梗死区(IS)的体积、心肌梗死面积以IS/AAR表示;检测血浆降钙素基因相关肽(calcitonin gene related peptide,CGRP);测定海马组织钙调蛋白;测定下丘脑室旁核、心肌缺血区和非缺血区P物质的表达。结果与CON组相比,MPC组的IS和IS/AAR均明显下降(P<0.01),TFP+MPC组分别与TFP组和CON组相比差异无显著性(P>0.05),而均明显高于MPC组(P<0.01);CON组分别与Sham组和MPC组相比,其下丘脑室旁核、心肌缺血区和非缺血区P物质表达均明显增高(P<0.01,P<0.05);MPC组血浆降钙素基因相关肽CGRP水平与海马钙调蛋白的表达均明显高于其它各组(P<0.01)。结论侧脑室内注射吗啡预处理对在体大鼠心肌缺血/再灌注损伤具有保护作用,其机制可能与钙调蛋白介导释放CGRP和痛觉的干预有关。     

Role of calcitonin gene-related peptide in ischaemic preconditioning in diabetic rat hearts

1. It has been suggested that calcitonin gene-related peptide (CGRP) is involved in the protection provided by ischaemic preconditioning in rat hearts and that ischaemic preconditioning is absent in diabetic rat hearts. 2. In the present study, we tested the relationship between sensory nerve function and ischaemic preconditioning in diabetic rats. 3. In 4- and 8-week diabetic rats and age-matched non- diabetic controls, 30 min global ischaemia and 40 min reperfusion caused a significant decrease in cardiac function and a marked increase in creatine kinase (CK) release. Ischaemic preconditioning, by three cycles of 5 min ischaemia and 5 min reperfusion, improved the recovery of cardiac function and decreased CK release during reperfusion in 4-week diabetic rat hearts. However, the cardioprotection afforded by ischaemic preconditioning was lost in 8-week diabetic rat hearts. Pretreatment with CGRP for 5 min also significantly improved the recovery of cardiac function and decreased CK release in rats subjected to 4 or 8 weeks of diabetes. 4. The content of CGRP in the coronary effluent during ischaemic preconditioning was significantly increased in 4-week diabetic rat hearts (P < 0.05). However, only a slight increase in the release of CGRP was shown in 8-week diabetic rat hearts (P > 0.05). 5. In summary, the present results suggest that the protection afforded by ischaemic preconditioning is attenuated in diabetic rats and that the change may be related to the reduction in CGRP release in diabetic rat hearts.     

Involvement of alpha-calcitonin gene-related peptide in heat stress-induced delayed preconditioning in rat hearts

1. Previous studies have shown that hyperthermia is capable of activating capsaicin-sensitive sensory nerves and stimulating the release of neurotransmitters from their peripheral terminals. Calcitonin gene-related peptide (CGRP) has recently been found to participate in delayed cardioprotection in rat isolated hearts. 2. The purpose of the present study was to explore whether the delayed cardioprotection by heat stress in vivo involves the expression and release of CGRP. 3. Sprague-Dawley rats were pretreated with whole-body hyperthermia (rectal 42 degrees C) for 15 min, 24 h before the experiments and then the left main coronary artery of rat hearts was subjected to a 45 min occlusion followed by 3 h reperfusion. The degree of myocardial injury was evaluated by measurement of infarct size and plasma creatine kinase (CK) activity. The plasma levels of CGRP and expression of CGRP (alpha and beta isoforms) mRNA in lumbar dorsal root ganglia at 4, 8, 16 or 24 h after heat stress treatment were measured. 4. Pretreatment with hyperthermia significantly reduced infarct size and CK release. Heat stress also significantly increased plasma concentrations of CGRP and the expression of alpha-CGRP mRNA, but not beta-CGRP mRNA. The effect of heat stress was completely abolished by pretreatment with capsaicin (50 mg/kg, s.c.), which selectively depletes transmitters in capsaicin-sensitive sensory nerves. 5. In summary, the results suggest that the delayed cardioprotection by heat stress involves the synthesis and release of CGRP and that the protection is mainly mediated by the alpha-CGRP isoform.     

靶向脂质体携载降钙素基因相关肽对大鼠主动脉内皮剥脱的保护作用

目的观察靶向脂质体携载降钙素基因相关肽（ｃａｌ－ｃｉｔｏｎｉｎｇｅｎｅ－ｒｅｌａｔｅｄｐｅｐｔｉｄｅ，ＣＧＲＰ）对大鼠主动脉内皮剥脱的保护作用。方法血管条灌流；放射免疫测定环磷酸鸟苷（ｃＧＭＰ）和内皮素（ｅｎｄｏｔｈｅｌｉｎ，ＥＴ）。结果由静脉注射靶向脂质体（ｌｉｐｏｓｏｍｅ，Ｌｓ）携载ＣＧＲＰ制备液（ＲＧＤＳ－Ｌｓ－ＣＧＲＰ６．２５μｇ·ｋｇ－１）能显著改善血管对乙酰胆碱（Ａｃｈ）的舒张反应（Ｐ＜０．０１），提高血浆ＮＯ－２含量（Ｐ＜０．０５）及主动脉组织中ｃＧＭＰ的含量（Ｐ＜０．０１），降低血浆ＥＴ含量（Ｐ＜０．０１）；抑制平滑肌细胞的过度增殖（Ｐ＜０．０１）。治疗作用明显优于相同剂量单纯ＣＧＲＰ组。结论靶向脂质体携载ＣＧＲＰ对冠状动脉再狭窄的发生具有一定的治疗作用，对临床治疗冠状动脉再狭窄提供一种新的给药方法