The cardioprotective effect of ischemic preconditioning (IPC) and ischemic postconditioning (IPoC) in adult hearts is mediated by nitric oxide (NO). During the early developmental period, rat hearts exhibit higher resistance to ischemia-reperfusion (I/R) injury, contain higher levels of serum nitrates, and their resistance cannot be further increased by IPC or IPoC. NOS blocker (L-NAME) lowers their high resistance. Wistar rat hearts (postnatal Days 1 and 10) were perfused according to Langendorff and exposed to 40 min of global ischemia followed by reperfusion with or without IPoC. NO and reactive oxygen species donors (DEA-NONO, SIN-1) and L-NAME were administered. Tolerance to ischemia decreased between Days 1 and 10. DEA-NONO (low concentrations) significantly increased tolerance to I/R injury on both Days 1 and 10. SIN-1 increased tolerance to I/R injury on Day 10, but not on Day 1. L-NAME significantly reduced resistance to I/R injury on Day 1, but actually increased resistance to I/R injury on Day 10. Cardioprotection by IPoC on Day 10 was not affected by either NO donors or L-NAME. It can be concluded that resistance of the neonatal heart to I/R injury is NO dependent, but unlike in adult hearts, cardioprotective interventions, such as IPoC, are most likely NO independent.
- MeSH
- donory oxidu dusnatého farmakologie MeSH
- ischemické přivykání metody MeSH
- ischemický postconditioning * metody MeSH
- krysa rodu rattus MeSH
- molsidomin farmakologie analogy a deriváty MeSH
- myokard metabolismus MeSH
- NG-nitroargininmethylester * farmakologie MeSH
- novorozená zvířata * MeSH
- oxid dusnatý * metabolismus MeSH
- potkani Wistar * MeSH
- reperfuzní poškození myokardu * prevence a kontrola metabolismus MeSH
- srdce účinky léků MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Increased level of C-reactive protein (CRP) is a risk factor for cardiovascular diseases, including myocardial infarction and hypertension. Here, we analyzed the effects of CRP overexpression on cardiac susceptibility to ischemia/reperfusion (I/R) injury in adult spontaneously hypertensive rats (SHR) expressing human CRP transgene (SHR-CRP). Using an in vivo model of coronary artery occlusion, we found that transgenic expression of CRP predisposed SHR-CRP to repeated and prolonged ventricular tachyarrhythmias. Excessive ischemic arrhythmias in SHR-CRP led to a significant reduction in infarct size (IS) compared with SHR. The proarrhythmic phenotype in SHR-CRP was associated with altered heart and plasma eicosanoids, myocardial composition of fatty acids (FAs) in phospholipids, and autonomic nervous system imbalance before ischemia. To explain unexpected IS-limiting effect in SHR-CRP, we performed metabolomic analysis of plasma before and after ischemia. We also determined cardiac ischemic tolerance in hearts subjected to remote ischemic perconditioning (RIPer) and in hearts ex vivo. Acute ischemia in SHR-CRP markedly increased plasma levels of multiple potent cardioprotective molecules that could reduce IS at reperfusion. RIPer provided IS-limiting effect in SHR that was comparable with myocardial infarction observed in naïve SHR-CRP. In hearts ex vivo, IS did not differ between the strains, suggesting that extra-cardiac factors play a crucial role in protection. Our study shows that transgenic expression of human CRP predisposes SHR-CRP to excess ischemic ventricular tachyarrhythmias associated with a drop of pump function that triggers myocardial salvage against lethal I/R injury likely mediated by protective substances released to blood from hypoxic organs and tissue at reperfusion.
- MeSH
- akční potenciály MeSH
- C-reaktivní protein genetika metabolismus MeSH
- fibrilace komor etiologie metabolismus patofyziologie MeSH
- hypertenze komplikace metabolismus patofyziologie MeSH
- komorová tachykardie etiologie metabolismus patofyziologie MeSH
- krevní tlak MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- myokard metabolismus patologie MeSH
- potkani inbrední SHR MeSH
- potkani transgenní MeSH
- reperfuzní poškození myokardu etiologie metabolismus patofyziologie prevence a kontrola MeSH
- srdeční frekvence MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Cangrelor je jediným nitrožilním inhibitorem destičkového receptoru pro adenosindifosfát typu P2Y12 s klinicky prokázanou účinností pro snížení ischemických komplikací koronární angioplastiky (percutaneous coronary intervention, PCI). Přestože doporučenou indikací pro jeho použití je každá PCI u pacientů neléčených perorálními inhibitory P2Y12, v klinické praxi je používán dominantně pro rizikové výkony při akutním koronárním syndromu. Hlavní výhodou jeho podání při léčbě infarktu myokardu PCI je jeho rychlý a dobře předvídatelný protidestičkový účinek, nicméně experimentální studie ukazují navíc významný vliv cangreloru na ochranu myokardu před reperfuzním poškozením. Slibné teoretické výhody cangreloru pro použití při léčbě infarktu myokardu čekají na potvrzení v klinických studiích.
Cangrelor is the only intravenous platelet P2Y12 receptor inhibitor that has proven clinical efficacy in reducing coronary angioplasty (percutaneous coronary intervention, PCI) - related ischemic complications. Despite being recommended to all P2Y12-naive patients, cangrelor is preferentially used in routine clinical practice for high-risk PCI's in acute coronary syndrome. The fast and predictable antiplatelet action creates the optimal conditions for PCI treatment of myocardial infarction, but in addition, cangrelor offers a cardioprotective effect against reperfusion injury in many animal models. The promising position of cangrelor in treating myocardial infarction needs to be confirmed by large randomized clinical trials.
- Klíčová slova
- Kangrelor,
- MeSH
- adenosinmonofosfát analogy a deriváty MeSH
- infarkt myokardu * farmakoterapie MeSH
- inhibitory agregace trombocytů farmakologie terapeutické užití MeSH
- koronární angioplastika metody MeSH
- lidé MeSH
- purinergní receptory P2Y - antagonisté * farmakologie terapeutické užití MeSH
- reperfuze myokardu metody MeSH
- reperfuzní poškození myokardu prevence a kontrola MeSH
- ticagrelor terapeutické užití MeSH
- Check Tag
- lidé MeSH
The role of opioid kappa1 and kappa2 receptors in reperfusion cardiac injury was studied. Male Wistar rats were subjected to a 45-min coronary artery occlusion followed by a 120-min reperfusion. Opioid kappa receptor agonists were administered intravenously 5 min before the onset of reperfusion, while opioid receptor antagonists were given 10 min before reperfusion. The average value of the infarct size/area at risk (IS/AAR) ratio was 43 - 48% in untreated rats. Administration of the opioid kappa1 receptor agonist (-)-U-50,488 (1 mg/kg) limited the IS/AAR ratio by 42%. Administration of the opioid kappa receptor agonist ICI 199,441 (0.1 mg/kg) limited the IS/AAR ratio by 41%. The non-selective opioid kappa receptor agonist (+)-U-50,488 (1 mg/kg) with low affinity for opioid kappa receptor, the peripherally acting opioid kappa2 receptor agonist ICI 204,448 (4 mg/kg) and the selective opioid ?2 receptor agonist GR89696 (0.1 mg/kg) had no effect on the IS/AAR ratio. Pretreatment with naltrexone, the peripherally acting opioid receptor antagonist naloxone methiodide, or the selective opioid kappa2 receptor antagonist nor-binaltorphimine completely abolished the infarct-reducing effect of (-)-U-50,488 and ICI 199,441. Pretreatment with the selective opioid ? receptor antagonist TIPP[psi] and the selective opioid μ receptor antagonist CTAP did not alter the infarct reducing effect of (-)-U-50,488 and ICI 199,441. Our study is the first to demonstrate the following: (a) the activation of opioid kappa2 receptor has no effect on cardiac tolerance to reperfusion; (b) peripheral opioid kappa1 receptor stimulation prevents reperfusion cardiac injury; (c) ICI 199,441 administration resulted in an infarct-reducing effect at reperfusion; (e) bradycardia induced by opioid kappa receptor antagonists is not dependent on the occupancy of opioid kappa receptor.
- MeSH
- 3,4-dichlor-N-methyl-N-(2-(1-pyrrolidinyl)-cyklohexyl)-benzenacetamid, (trans)-isomer aplikace a dávkování toxicita MeSH
- infarkt myokardu metabolismus patologie prevence a kontrola MeSH
- intravenózní podání MeSH
- kardiomyocyty účinky léků metabolismus patologie MeSH
- modely nemocí na zvířatech MeSH
- narkotika - antagonisté aplikace a dávkování MeSH
- opioidní analgetika aplikace a dávkování toxicita MeSH
- piperaziny aplikace a dávkování MeSH
- potkani Wistar MeSH
- pyrrolidiny aplikace a dávkování toxicita MeSH
- receptory opiátové kappa agonisté metabolismus MeSH
- reperfuzní poškození myokardu metabolismus patologie prevence a kontrola MeSH
- signální transdukce MeSH
- srdeční arytmie chemicky indukované patofyziologie MeSH
- srdeční frekvence účinky léků MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Chronic continuous normobaric hypoxia (CNH) increases cardiac tolerance to ischemia/reperfusion injury in vivo and this effect is mediated via µ and delta2 opioid receptors (ORs) activation. CNH has also been shown to be cardioprotective in isolated rat heart. In this study, we hypothesize that this cardioprotective effect of CNH is mediated by activation of µ and delta2 ORs and preservation of mitochondrial function. Hearts from rats adapted to CNH (12 % oxygen) for 3 weeks were extracted, perfused in the Langendorff mode and subjected to 45 min of global ischemia and 30 min of reperfusion. Intervention groups were pretreated for 10 min with antagonists for different OR types: naloxone (300 nmol/l), the selective delta OR antagonist TIPP(psi) (30 nmol/l), the selective delta1 OR antagonist BNTX (1 nmol/l), the selective delta2 OR antagonist naltriben (1 nmol/l), the selective peptide µ OR antagonist CTAP (100 nmol/l) and the selective delta OR antagonist nor-binaltorphimine (3 nmol/l). Creatine kinase activity in coronary effluent and cardiac contractile function were monitored to assess cardiac injury and functional impairment. Additionally, cardiac tissue was collected to measure ATP and to isolate mitochondria to measure respiration rate and calcium retention capacity. Adaptation to CNH decreased myocardial creatine kinase release during reperfusion and improved the postischemic recovery of contractile function. Additionally, CNH improved mitochondrial state 3 and uncoupled respiration rates, ADP/O, mitochondrial transmembrane potential and calcium retention capacity and myocardial ATP level during reperfusion compared to the normoxic group. These protective effects were completely abolished by naloxone, TIPP(psi), naltriben, CTAP but not BNTX or nor-binaltorphimine. These results suggest that cardioprotection associated with adaptation to CNH is mediated by µ and delta2 opioid receptors activation and preservation of mitochondrial function.
- MeSH
- hypoxie patofyziologie MeSH
- krysa rodu rattus MeSH
- narkotika - antagonisté farmakologie MeSH
- orgánové kultury - kultivační techniky MeSH
- potkani Wistar MeSH
- receptory opiátové delta antagonisté a inhibitory fyziologie MeSH
- receptory opiátové mu antagonisté a inhibitory fyziologie MeSH
- reperfuzní poškození myokardu patofyziologie prevence a kontrola MeSH
- srdeční mitochondrie účinky léků fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Cardioprotective effect of ischemic preconditioning (IPC) and ischemic postconditioning (IPoC) in adult hearts is mediated by mitochondrial-K-ATP channels and nitric oxide (NO). During early developmental period, rat hearts exhibit higher resistance to ischemia-reperfusion (I/R) injury and their resistance cannot be further increased by IPC or IPoC. Therefore, we have speculated, whether mechanisms responsible for high resistance of neonatal heart may be similar to those of IPC and IPoC. To test this hypothesis, rat hearts isolated on days 1, 4, 7, and 10 of postnatal life were perfused according to Langendorff. Developed force (DF) of contraction was measured. Hearts were exposed to 40 min of global ischemia followed by reperfusion up to the maximum recovery of DF. IPoC was induced by 5 cycles of 10-s ischemia. Mito-K-ATP blocker (5-HD) was administered 5 min before ischemia and during first 20 min of reperfusion. Another group of hearts was isolated for biochemical analysis of 3-nitrotyrosine, and serum samples were taken to measure nitrate levels. Tolerance to ischemia did not change from day 1 to day 4 but decreased on days 7 and 10. 5-HD had no effect either on neonatal resistance to I/R injury or on cardioprotective effect of IPoC on day 10. Significant difference was found in serum nitrate levels between days 1 and 10 but not in tissue 3-nitrotyrosine content. It can be concluded that while there appears to be significant difference of NO production, mito-K-ATP and ROS probably do not play role in the high neonatal resistance to I/R injury.
- MeSH
- draslíkové kanály metabolismus MeSH
- ischemický postconditioning * MeSH
- krysa rodu rattus MeSH
- novorozená zvířata MeSH
- oxid dusnatý metabolismus MeSH
- potkani Wistar MeSH
- reperfuzní poškození myokardu metabolismus patofyziologie prevence a kontrola MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Epoxyeicosatrienoic acids (EETs) decrease cardiac ischemia-reperfusion injury; however, the mechanism of their protective effect remains elusive. Here, we investigated the cardioprotective action of a novel EET analog, EET-B, in reperfusion and the role of hypoxia-inducible factor (HIF)-1α in such action of EET-B. Adult male rats were subjected to 30 min of left coronary artery occlusion followed by 2 h of reperfusion. Administration of 14,15-EET (2.5 mg/kg) or EET-B (2.5 mg/kg) 5 min before reperfusion reduced infarct size expressed as a percentage of the area at risk from 64.3 ± 1.3% in control to 42.6 ± 1.9% and 46.0 ± 1.6%, respectively, and their coadministration did not provide any stronger effect. The 14,15-EET antagonist 14,15-epoxyeicosa-5( Z)-enoic acid (2.5 mg/kg) inhibited the infarct size-limiting effect of EET-B (62.5 ± 1.1%). Similarly, the HIF-1α inhibitors 2-methoxyestradiol (2.5 mg/kg) and acriflavine (2 mg/kg) completely abolished the cardioprotective effect of EET-B. In a separate set of experiments, the immunoreactivity of HIF-1α and its degrading enzyme prolyl hydroxylase domain protein 3 (PHD3) were analyzed in the ischemic areas and nonischemic septa. At the end of ischemia, the HIF-1α immunogenic signal markedly increased in the ischemic area compared with the septum (10.31 ± 0.78% vs. 0.34 ± 0.08%). After 20 min and 2 h of reperfusion, HIF-1α immunoreactivity decreased to 2.40 ± 0.48% and 1.85 ± 0.43%, respectively, in the controls. EET-B blunted the decrease of HIF-1α immunoreactivity (7.80 ± 0.69% and 6.44 ± 1.37%, respectively) and significantly reduced PHD3 immunogenic signal in ischemic tissue after reperfusion. In conclusion, EET-B provides an infarct size-limiting effect at reperfusion that is mediated by HIF-1α and downregulation of its degrading enzyme PHD3. NEW & NOTEWORTHY The present study shows that EET-B is an effective agonistic 14,15-epoxyeicosatrienoic acid analog, and its administration before reperfusion markedly reduced myocardial infarction in rats. Most importantly, we demonstrate that increased hypoxia-inducible factor-1α levels play a role in cardioprotection mediated by EET-B in reperfusion likely by mechanisms including downregulation of the hypoxia-inducible factor -1α-degrading enzyme prolyl hydroxylase domain protein 3.
- MeSH
- down regulace MeSH
- faktor 1 indukovatelný hypoxií - podjednotka alfa genetika metabolismus MeSH
- funkce levé komory srdeční účinky léků MeSH
- infarkt myokardu enzymologie patologie patofyziologie prevence a kontrola MeSH
- kyselina 8,11,14-eikosatrienová analogy a deriváty farmakologie MeSH
- modely nemocí na zvířatech MeSH
- myokard enzymologie patologie MeSH
- potkani Sprague-Dawley MeSH
- prolyl-4-hydroxylasy HIF genetika metabolismus MeSH
- proteolýza MeSH
- remodelace komor účinky léků MeSH
- reperfuzní poškození myokardu enzymologie patologie patofyziologie prevence a kontrola MeSH
- signální transdukce účinky léků MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Currently, there are no satisfactory interventions to protect the heart against the detrimental effects of ischemia-reperfusion injury. Although ischemic preconditioning (PC) is the most powerful form of intrinsic cardioprotection, its application in humans is limited to planned interventions, due to its short duration and technical requirements. However, many organs/tissues are capable of producing "remote" PC (RPC) when subjected to brief bouts of ischemia-reperfusion. RPC was first described in the heart where brief ischemia in one territory led to protection in other area. Later on, RPC started to be used in patients with acute myocardial infarction, albeit with ambiguous results. It is hypothesized that the connection between the signal triggered in remote organ and protection induced in the heart can be mediated by humoral and neural pathways, as well as via systemic response to short sublethal ischemia. However, although RPC has a potentially important clinical role, our understanding of the mechanistic pathways linking the local stimulus to the remote organ remains incomplete. Nevertheless, RPC appears as a cost-effective and easily performed intervention. Elucidation of protective mechanisms activated in the remote organ may have therapeutic and diagnostic implications in the management of myocardial ischemia and lead to development of pharmacological RPC mimetics.
- MeSH
- časové faktory MeSH
- infarkt myokardu metabolismus patologie patofyziologie prevence a kontrola MeSH
- ischemické přivykání metody MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- myokard metabolismus patologie MeSH
- regionální krevní průtok MeSH
- reperfuzní poškození myokardu metabolismus patologie patofyziologie prevence a kontrola MeSH
- signální transdukce MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Řízená reperfuze s cílem snížit ischemicko-reperfuzní posškození, kdy se pomocí manžety tonometru vyvolá ischemie tkání vzdálených od myokardu u pacientů se STEMI směrovanými k reperfuzní léčbě, snižuje morbiditu a mortalitu. Je to jednoduchá technika proveditelná jak v sanitním voze tak na urgentním příjmu, zatímco je pacient připravován k perkutánní koronární intervenci; snižuje riziko akutního poškození ledvin, signifikantně snižuje rozsah poškození myokardu při infarktu a snižuje riziko srdečního selhání a dysrytmií během intervence i po ní. Tyto účinky přetrvávají ještě delší dobu po zákroku a u pacientů je nižší pravděpodobnost další koronární nebo mozkové příhody v následujících měsících až letech. Kromě snížené mortality a lepší kvality života přináší metoda i měřitelné snížení nákladů vynaložených na zdravotní péči.
EMS of Central Bohemian Region had introduced the board portable ultrasonography devices for use in daily practice in the prehospital emergency care. The devices used are compact ultrasonographs GE-VScan with dual sector/linear probe. The devices were placed at EMS district stations. This article describes the scheme of training, possibilities of practical use for diagnostics and therapeutical procedures in EMS practice. We use modified emergency protocols FATE, FEEL, BLUE and FAST. The author describes individual clinical training in hospitals under supervision of clinical specialists which is provided after initial traininng. The first experience during 3 and half months´s praktice since start of this project are also described. Based on the ultrasound examination therapeutical management had been changed in 5 cases and once the difficult i.v. ultrasound guided access was in the field.
- MeSH
- infarkt myokardu chirurgie MeSH
- ischemické přivykání * metody MeSH
- koronární angioplastika MeSH
- lidé MeSH
- pooperační komplikace prevence a kontrola MeSH
- reperfuze myokardu metody MeSH
- reperfuzní poškození myokardu prevence a kontrola MeSH
- urgentní zdravotnické služby metody MeSH
- Check Tag
- lidé MeSH
A 2×2 factorial design was used to evaluate possible preservation of mitochondrial functions in two cardioprotective experimental models, remote ischemic preconditioning and streptozotocin-induced diabetes mellitus, and their interaction during ischemia/reperfusion injury (I/R) of the heart. Male Wistar rats were randomly allocated into four groups: control (C), streptozotocin-induced diabetic (DM), preconditioned (RPC) and preconditioned streptozotocin-induced diabetic (DM+RPC). RPC was conducted by 3 cycles of 5-min hind-limb ischemia and 5-min reperfusion. DM was induced by a single dose of 65 mg/kg streptozotocin. Isolated hearts were exposed to ischemia/reperfusion test according to Langendorff. Thereafter mitochondria were isolated and the mitochondrial respiration was measured. Additionally, the ATP synthase activity measurements on the same preparations were done. Animals of all groups subjected to I/R exhibited a decreased state 3 respiration with the least change noted in DM+RPC group associated with no significant changes in state 2 respiration. In RPC, DM and DM+RPC group, no significant changes in the activity of ATP synthase were observed after I/R injury. These results suggest that the endogenous protective mechanisms of RPC and DM do preserve the mitochondrial function in heart when they act in combination.
- MeSH
- experimentální diabetes mellitus metabolismus MeSH
- ischemické přivykání metody MeSH
- krysa rodu rattus MeSH
- myokard metabolismus MeSH
- náhodné rozdělení MeSH
- potkani Wistar MeSH
- reperfuzní poškození myokardu metabolismus prevence a kontrola MeSH
- spotřeba kyslíku fyziologie MeSH
- srdeční mitochondrie fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH