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Basarab DA, Kozhura VL, Golubev AM, Timkina MI, Moroz VV. [Effects of perftoran on experimental acute intestinal ischemia]. ANESTEZIOLOGIIA I REANIMATOLOGIIA 2002:31-6. [PMID: 12611154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
The studies were carried out on 76 albino noninbred male rats weighing 210-420 g. Ischemia of a jejunal segment was induced by applying a tourniquet to the base of a loop with the mesentery until the circulation fully stopped. Nonoxygenated perfluorane (an experimental group) or saline solution (a control group) was injected in a dose of 0.8-1.0 ml/100 g intraarterially 15 minutes before the termination of ischemia. During 90 min of reperfusion, there was a progressive decline of blood pressure (BP) with reference to the ischemic period by 39.8 +/- 20.9 and 20.8 +/- 14.6% in an experimental and control groups, respectively (p > 0.05). Biomicroscopy indicated that by min 5 of reperfusion, a relative reduction in the diameter (50-400 microns) of nutrient mesenteric arteries was half as large as that in the control group (24.0 +/- 5.5 and 45.1 +/- 3.6%; p < 0.05); by min 90, differences decreased (41.5 +/- 4.2 and 50.3 +/- 2.8%, respectively; p > or = 0.05). In the experimental group, perfluorane prevents the development of irreversible structural changes in the reperfusion period: the remaining cryptal epithelium is a source of regeneration of the integumentary epithelium of forming villi of the small intestinal mucosa.
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Murphy E, Cross HR, Steenbergen C. Is Na/Ca exchange during ischemia and reperfusion beneficial or detrimental? Ann N Y Acad Sci 2002; 976:421-30. [PMID: 12502591 DOI: 10.1111/j.1749-6632.2002.tb04771.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cytosolic calcium increases to approximately 3 micro M after 15 min of global ischemia. Manipulations that attenuate this increase in cytosolic Ca(2+) reduce myocyte death and dysfunction. The increase in cytosolic Ca(2+) during ischemia is dependent on an increase in intracellular Na(+), suggesting a role for Na/Ca exchange. Typical ischemic values for ionized intra- and extracellular Na(+), Ca(2+), and membrane potential are consistent with the Na/Ca exchanger operating near equilibrium during ischemia. Studies were undertaken using hearts from mice that overexpress the Na/Ca exchanger to determine if Na/Ca exchanger overexpression enhances or reduces ischemic injury. These studies suggest that overexpression of the Na/Ca exchanger enhances injury in males, but females are protected by a gender-related mechanism.
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Richard V, Laude K, Artigues C, Kaeffer N, Henry JP, Thuillez C. Heat stress increases endothelium-dependent relaxations and prevents reperfusion-induced endothelial dysfunction. Clin Exp Pharmacol Physiol 2002; 29:956-62. [PMID: 12366385 DOI: 10.1046/j.1440-1681.2002.03759.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. Heat stress has been widely used to stimulate the expression of stress proteins and is associated with various cardiovascular changes, including anti-ischaemic effects. However, the effect of heat stress on endothelial function is less clear. 2. Heat stress was induced in anaesthetized rats by increasing body temperature to 42 degrees C for 15 min. Twenty-four hours later, segments of rat aorta and mesenteric and coronary arteries were mounted in organ chambers. 3. Heat stress markedly increased relaxation to acetylcholine (ACh) in all three blood vessels studied, without affecting the response to the nitric oxide (NO) donor sydnonimine-1. 4. Heat stress also increased aortic relaxation to histamine and the calcium ionophore A23187. 5. In the aorta, an inhibitor of NO synthesis abolished the response to ACh in both control and heat stressed-rings, whereas a cyclo-oxygenase inhibitor had no effect. 6. Heat stress also prevented completely the impaired response to ACh in coronary arteries isolated from rats subjected to myocardial ischaemia and reperfusion. 7. Thus, heat stress increases the stimulated release of NO the rat aorta and mesenteric and coronary arteries and prevents reperfusion-induced injury at the level of the coronary endothelium.
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1754
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Shinoda M, Shimazu M, Wakabayashi G, Tanabe M, Hoshino K, Kitajima M. Tumor necrosis factor suppression and microcirculatory disturbance amelioration in ischemia/reperfusion injury of rat liver after ischemic preconditioning. J Gastroenterol Hepatol 2002; 17:1211-9. [PMID: 12453282 DOI: 10.1046/j.1440-1746.2002.02864.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Brief periods of hepatic ischemia produce immediate tolerance for subsequent prolonged ischemia. Although the beneficial effect of this ischemic preconditioning is recognized, the mechanism itself remains poorly understood. METHODS Male Wistar rats were divided into two groups: a control group that was subjected to 30 min of ischemia + following reperfusion, and an ischemic preconditioning group that was subjected to 5 min of ischemia + 5 min of reperfusion + 30 min of ischemia + following reperfusion. By using this model, hepatic damage, microcirculatory disturbances, and tumor necrosis factor-alpha protein production and mRNA expression were analyzed during the course of reperfusion in both groups. For the hepatic damage evaluations, hepatic enzyme levels, histology, apoptosis analysis, and intravital microfluorography for dead cells were examined. For the microcirculatory disturbance analysis, an adhesion molecule and intravital microfluorography for endothelial-adherent leukocytes were examined. RESULTS In the ischemic preconditioning group, ischemia/reperfusion injuries (shown by hepatic enzymes elevation, histological degeneration, and increases in the number of apoptotic cells and microfluorographic dead cells) were markedly reduced. Moreover, microcirculatory disturbances represented by intercellular adhesion molecule-1 expression and leukocyte adhesion on the endothelium were ameliorated. Tumor necrosis factor-alpha protein production and mRNA expression were also suppressed in the ischemic preconditioning group. CONCLUSION The suppression of tumor necrosis factor-alpha and the subsequent amelioration of microcirculatory disturbances were observed, suggesting that the mechanism underlying the protective effect of ischemic preconditioning in hepatic ischemia/reperfusion injuries may involve tumor necrosis factor-alpha and microcirculatory regulation.
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1755
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Uzan A. [Thrombosis and ischemia: experimental data]. ARCHIVES DES MALADIES DU COEUR ET DES VAISSEAUX 2002; 95 Spec No 7:31-5. [PMID: 12500602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Thrombosis and ischaemia are often linked to an atherosclerotic arterial lesion. An inflammatory process implicating leucocytes and inflammation mediators (cytokines) as well as atheroma plaque rupture liberating tissue factor are at the origin of this pathology. Equally, blood platelets play an important role, not only with the formation of platelet aggregates, but also by their procoagulant action resulting from the exposure of membrane phospholipids. Apoptotic cells release procoagulant microparticles from the plaque, favouring thrombogenesis. In this context reperfusion would a priori restore blood flow, but it is also the origin of cytotoxicity due to the sudden release of necrotising factors. Various animal models are used to experimentally reproduce arterial thrombosis either following or not following ischaemia/reperfusion. Among them the model of progressive coronary occlusion by intraluminal electrical stimulation, the model of quasi-instantaneous thrombosis by the introduction of a copper coil, and the model of ischaemia/reperfusion by occlusion of the left descending coronary for 90 minutes followed by reperfusion have been studied more precisely in the dog. In the rat, cerebral ischaemia followed by reperfusion has been provoked with occlusion of the middle cerebral artery. The studies in dogs show that Enoxaparine significantly reduces the formation of coronary thrombus induced progressively by an anodal current and potentiates the action of the tissular activator plasminogen (t-PA) on a recently formed thrombus. At the level of myocardial ischaemia. Enoxaparine reduces the extent of infarction as well as the neutrophil and platelet accumulation in the infarcted zone or in at risk zone. This effect seems to correlate with an anti-inflammatory type action demonstrated elsewhere in vitro with platelet/neutrophil adhesion in the presence of P-Selectin. In all of these studies standard heparin used under the same conditions proves to be inactive. In the ischaemia/reperfusion model in the dog, aspirin has been shown to be ineffective up to a dose of 6 mg/Kg. Enoxaparine is an example of a possible double anti-thrombotic and anti-ischaemic component in the prevention of disorders caused by the thrombosis-ischaemia-reperfusion triad.
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D'Ambrosio AL, Hoh DJ, Mack WJ, Winfree CJ, Nair MN, Ducruet A, Sciacca RR, Huang J, Pinsky DJ, Connolly ES. Interhemispheric intracranial pressure gradients in nonhuman primate stroke. SURGICAL NEUROLOGY 2002; 58:295-301; discussion 301. [PMID: 12504286 DOI: 10.1016/s0090-3019(02)00817-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Although the development of significant interhemispheric intracranial pressure (ICP) gradients in the setting of unilateral stroke remains controversial, no study to date has investigated the existence of these gradients in a controlled, reproducible, clinically relevant model. Therefore, we used a primate model of reperfused hemispheric stroke to better characterize the development of these gradients. METHODS Bilateral intraparenchymal ICP was continuously monitored in 7 adult male baboons subjected to left hemisphere reperfused stroke. Interhemispheric ICP gradients were calculated for each baboon and plotted over time. Infarct volume was determined using T2-weighted magnetic resonance imaging (MRI) at sacrifice. RESULTS A bimodal distribution of interhemispheric ICP gradients was observed in animals with >20% infarct volume (22.1% +/- 0.9; range 21-23%) versus < or = 15% infarct volume (6.6% +/- 2.7; range 1-15%). In animals with >20% infarct volume, interhemispheric gradients developed early and persisted throughout the monitoring period. At 12 hours postreperfusion, animals with large infarcts demonstrated a mean pressure gradient of 13.8 +/- 4.3 mm Hg, compared to a mean gradient of -2.6 +/- 1.1 mm Hg for animals with < or =15% infarct volume. The difference in pressure gradients was statistically significant at all time points from 4 to 12 hours postreperfusion (p < 0.01). CONCLUSIONS These data suggest that, in nonhuman primates, infarcts of a size approaching 20% of the hemisphere may be associated with significant ICP gradients. With these larger infarcts, ipsilateral monitoring is required if regional cerebral perfusion pressure is to be accurately assessed.
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1757
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Cavalieri B, Perrelli MG, Aragno M, Mastrocola R, Corvetti G, Durazzo M, Poli G, Cutrìn JC. Ischemic preconditioning attenuates the oxidant-dependent mechanisms of reperfusion cell damage and death in rat liver. Liver Transpl 2002; 8:990-9. [PMID: 12424711 DOI: 10.1053/jlts.2002.35549] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In an in vivo rat model of liver ischemia followed by reperfusion a consistent appearance of necrosis and activation of biochemical pathways of apoptosis was reproduced and monitored after 30 minutes reperfusion. Preconditioning by application of a short cycle of ischemia-reperfusion (10 minutes + 10 minutes) positively conditioned recovery of the organ at reperfusion, attenuating both necrotic and apoptotic events. Preconditioning at least halved cell oxidative damage occurring early at reperfusion, and as a major consequence, the increase of cytolysis and apoptosis occurring at reperfusion was about 50% less. The attenuation of both pathways of cell death by preconditioning appeared at least partly related to its modulate action on H(2)O(2) and 4-hydroxy-2,3-trans-nonenal production. The overall data point to a marked diminished oxidant generation and oxidative reactions as one major possible mechanism through which ischemic preconditioning exerts protection against necrotic and apoptotic insult to the postischemic liver.
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1758
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Ahmed A, el-Kossi M, Raftery A, el-Nahas M, Haylor J. Renal warm ischaemic injury in the rat is potentiated by cyclosporine. Transplant Proc 2002; 34:2668-9. [PMID: 12431568 DOI: 10.1016/s0041-1345(02)03369-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Wallace JA, Alexander S, Estrada EY, Hines C, Cunningham LA, Rosenberg GA. Tissue inhibitor of metalloproteinase-3 is associated with neuronal death in reperfusion injury. J Cereb Blood Flow Metab 2002; 22:1303-10. [PMID: 12439287 DOI: 10.1097/01.wcb.0000040943.89393.c1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Programmed cell death occurs in ischemia when cell surface death receptors (DRs) are stimulated by death-inducing ligands (DILs). Matrix metalloproteinases are extracellular matrix-degrading enzymes involved in the shedding of DRs and DILs from the cell surface. Tissue inhibitor of metalloproteinase-3 (TIMP-3), which is bound to the extracellular matrix, has been shown to promote apoptosis in cancer cell lines by inhibiting cell surface sheddases. Since apoptosis is an important mechanism of cell death in ischemia, the authors hypothesized that TIMP-3 would be expressed in ischemic neurons that are undergoing programmed cell death. Spontaneously hypertensive rats had a 90-minute middle cerebral artery occlusion with reperfusion. Transcription of TIMP-3 mRNA was measured by quantitative reverse transcription-polymerase chain reaction at 2, 6, 24 and 48 hours after reperfusion. Western blots were used to measure TIMP-3 protein expression. Spatial distribution and production of TIMP-3 was studied by immunohistochemistry at 3, 24, and 48 hours, 5 days, and 3 weeks. DNA fragmentation in cells dying by necrosis and apoptosis was identified with terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate-biotin nick end labeling (TUNEL). After 2 hours of reperfusion, TIMP-3 mRNA increased significantly in both ischemic and nonischemic hemispheres. Western blot analysis confirmed the identity of the TIMP-3, which appeared to be increased on the ischemic side. After 3 hours of reperfusion, TIMP-3 immunostaining was increased in neurons on the ischemic side, and by 24 hours the majority of the ischemic neurons were TIMP-3-positive. Dual-fluorescence staining for TUNEL and TIMP-3 showed that they were coexpressed in many neurons. The results suggest that ischemic neurons express TIMP-3, which may be inhibiting sheddases. The authors propose that TIMP-3 facilitates cell death in ischemic neurons. Further studies are needed to identify the sheddases inhibited by the TIMP-3, and on the effect of inhibition of matrix metalloproteinases on cell death mechanisms.
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Nielsen VG, Geary BT. Coagulopathy mediated by hepatoenteric ischemia-reperfusion in rabbits: role of xanthine oxidase. Transplantation 2002; 74:1181-3. [PMID: 12438967 DOI: 10.1097/00007890-200210270-00021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Hepatic transplantation may result in coagulopathy caused by the release of mast-cell-derived heparin, and xanthine oxidase (XO) inhibition stabilizes mast cells. Thus, XO inactivation could decrease coagulopathy after hepatoenteric ischemia-reperfusion. Rabbits were fed a standard or XO-inactivating diet before hepatoenteric ischemia for 35 min and before 30 min of reperfusion. Hemostasis was assessed by thrombelastography. Heparin activity was quantified by anti-IIa. XO inactivation resulted in clot formation after reperfusion in all animals, whereas only 37.5% of animals with XO activity clotted (P<0.05). Anti-IIa activity was less in animals at baseline and after reperfusion with XO inactivation (45+/-5 and 65+/-5 mU/mL, respectively) compared to animals with XO activity (51+/-4 and 71+/-5 mU/mL, respectively) (P<0.05). Clot strength, which was mediated by coagulation proteins, was significantly greater at baseline and after reperfusion in animals with XO inactivation. XO inactivation enhances hemostasis by decreasing circulating heparin activity and increasing coagulation protein function before ischemia-reperfusion.
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Hoffmann SC, Kampen RL, Amur S, Sharaf MA, Kleiner DE, Hunter K, John Swanson S, Hale DA, Mannon RB, Blair PJ, Kirk AD. Molecular and immunohistochemical characterization of the onset and resolution of human renal allograft ischemia-reperfusion injury. Transplantation 2002; 74:916-23. [PMID: 12394831 DOI: 10.1097/00007890-200210150-00003] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Following allotransplantation, renal ischemia-reperfusion (I/R) injury initiates a series of events that provokes counter-adaptive immunity. Though T cells clearly mediate allospecific immunity, the manner in which reperfusion events augment their activation has not been established. In addition, comprehensive analysis of I/R injury in humans has been limited. METHODS To evaluate the earliest events occurring following allograft reperfusion and gain insight into those factors linking reperfusion to alloimmunity, we examined human renal allografts 30 to 60 minutes postreperfusion (n=10) and compared them with allografts with normal function that had resolved their I/R injury insult (>1 month posttransplant, n=6) and to normal kidneys (living donor kidneys before procurement, n=8). Biopsies were processed both for immunohistochemical analysis as well as for transcript analysis by real-time quantitative polymerase chain reaction (RT-PCR). RESULTS Reperfusion injury was characterized by increased levels of gene transcripts known to be involved in cellular adhesion, chemotaxis, apoptosis, and monocyte recruitment and activation. T-cell-associated transcripts were generally absent. However, recovered allografts exhibited increased levels of T-cell and costimulation-related gene transcripts despite normal allograft function. Consistent with these findings, the immediate postreperfusion state was characterized histologically by tubular injury and monocyte infiltration, while the stable posttransplant state was notable for T-cell infiltration. CONCLUSIONS These data suggest that monocytes and transcripts related to their recruitment dominate the immediate postreperfusion state. This gives way to a T-cell dominant milieu even in grafts selected for their stable function and absence of rejection. These data have implications for understanding the fundamental link between I/R injury and alloimmunity.
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Bozkurt AK. Alpha-tocopherol (Vitamin E) and iloprost attenuate reperfusion injury in skeletal muscle ischemia/reperfusion injury. THE JOURNAL OF CARDIOVASCULAR SURGERY 2002; 43:693-6. [PMID: 12386586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
BACKGROUND The aim of this study was to clarify the role of a-tocopherol (vitamin E) and iloprost on skeletal muscle ischemia/reperfusion injury. METHODS SETTING animal research laboratory of a university hospital. EXPERIMENTAL DESIGN the iliac arteries of the 24 adult Sprague-Dawley rats were clamped and 4 hours of ischemia followed by 1 hour of reperfusion was applied. In an attempt to decrease reperfusion injury, the rats were given either a-tocopherol (n=8), iloprost (n=6) and 8 rats were given normal saline and served as control group (n=8). MEASURES blood pH, pO2, pCO2, HCO3, Na, K, creatine kinase (CPK), lactate dehydrogenase (LDH) values were determined at the end of the reperfusion period. Malondialdehyde (MDA), a product of lipid peroxidation, was measured in blood, muscle and lung as an indicator of free radicals. RESULTS Blood pO2 and HCO3 levels were significantly high (p<0.05); CPK, LDH and MDA levels were significantly low (p<0.05) in both a-tocopherol and iloprost groups when compared to the control group. Similarly, the MDA levels in the gastrocnemius muscle were significantly low in both treatment groups when compared to the controls (p<0.05). There was no significant difference between groups in other parameters. CONCLUSIONS The results suggest that, both a-tocopherol and iloprost are useful for attenuating oxidative muscle damage occurring after a period of ischemia/ reperfusion.
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Amorim FF, Pinheiro Bd BDV, Romaldini H. Metabolic and hemodynamic effects of saline infusion to maintain volemia on temporary abdominal aortic occlusion. Arq Bras Cardiol 2002; 79:395-404. [PMID: 12426648 DOI: 10.1590/s0066-782x2002001300007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE To analyze hemodynamic and metabolic effects of saline solution infusion in the maintenance of blood volume in ischemia-reperfusion syndrome during temporary abdominal aortic occlusion in dogs. METHODS We studied 20 dogs divided into 2 groups: the ischemia-reperfusion group (IRG, n=10) and the ischemia-reperfusion group with saline solution infusion aiming at maintaining mean pulmonary arterial wedge pressure between 10 and 20 mmHg (IRG-SS, n=10). All animals were anesthetized with sodium thiopental and maintained on spontaneous ventilation. Occlusion of the supraceliac aorta was obtained with inflation of a Fogarty catheter inserted through the femoral artery. After 60 minutes of ischemia, the balloon was deflated, and the animals were observed for another 60 minutes of reperfusion. RESULTS IRG-SS dogs did not have hemodynamic instability after aortic unclamping, and the mean systemic blood pressure and heart rate were maintained. However, acidosis worsened, which was documented by a greater reduction of arterial pH that occurred especially due to the absence of a respiratory response to metabolic acidosis that was greater with the adoption of this procedure. CONCLUSION Saline solution infusion to maintain blood volume avoided hemodynamic instability after aortic unclamping. This procedure, however, caused worsening in metabolic acidosis in this experimental model.
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Müller V, Losonczy G, Heemann U, Vannay A, Fekete A, Reusz G, Tulassay T, Szabó AJ. Sexual dimorphism in renal ischemia-reperfusion injury in rats: possible role of endothelin. Kidney Int 2002; 62:1364-71. [PMID: 12234307 DOI: 10.1111/j.1523-1755.2002.kid590.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Postischemic organ dysfunction is influenced by gender and sexual steroids. METHODS To compare the susceptibility of the kidney to postischemic failure between sexes, the left vascular pedicle was clamped for 50 minutes in anesthetized male and female Wistar rats. Survival rate, renal and systemic hemodynamics and renal prepro-endothelin (pp-ET) mRNA expression were measured. RESULTS Eight percent of males as compared to 75% of females survived for more than 7 days. Previous orchidectomy of mature rats or sexual immaturity improved the rate of 7 day survival to 67% and 58%, respectively, as compared to intact males (P < 0.05). Estradiol treatment of mature male animals also resulted in a significantly better survival. Ovariectomy, sexual immaturity or testosterone treatment had no impact on the course of renal failure in females. The early postischemic recovery of renal blood flow was delayed due to a dramatic increase in renal vascular resistance in male versus female rats. The expression of pp-ET gene in the kidneys was increased at 5 minutes following reperfusion and was significantly higher 2 hours after ischemia in males, but not in females. Pretreatment with the endothelin A receptor antagonist LU 135252 provided indistinguishable survival rates in intact male and female rats after warm renal ischemia. CONCLUSION Female rats enjoy relative protection against postischemic renal failure. Furthermore, in intact males the effects of androgens upon ischemic kidney damage seem to be mediated by endothelin-induced vascular changes.
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Shashikant MP, Badellino MM, Cooper B, Shaffer TH, Myers SI, Wolfson MR. Physicochemical properties of perfluorochemical liquids influence ventilatory requirements, pulmonary mechanics, and microvascular permeability during partial liquid ventilation following intestinal ischemia/reperfusion injury. Crit Care Med 2002; 30:2300-5. [PMID: 12394959 DOI: 10.1097/00003246-200210000-00019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To test the hypothesis that the physicochemical properties of perfluorochemical liquid used in partial liquid ventilation can influence ventilatory requirements, pulmonary mechanics, microvascular permeability, and vasoactive mediator release in the abnormal lung. DESIGN Prospective, controlled animal study. SETTING Research laboratory in a university setting. SUBJECTS Male Sprague-Dawley rats: sham and intestinal ischemia/reperfusion injury. INTERVENTIONS Treatment with perfluorochemical partial liquid ventilation (PLV: PP-5 or H-130) or conventional mechanical ventilation (CMV) over 60 mins of superior mesenteric artery occlusion and 60 mins of reperfusion. MEASUREMENTS AND MAIN RESULTS Gas exchange, ventilatory requirements, and pulmonary mechanics were measured in vivo. Subsequently, pulmonary vascular resistance, microvascular permeability, and thromboxane were measured by using the isolated perfused lung preparation. PLV with PP-5 required significantly (p <.05) higher positive end-expiratory pressure resulting in increased mean airway pressures and pulmonary vascular resistance in both sham and intestinal ischemia/reperfusion injured animals compared with those treated with CMV or PLV H-130. PLV PP-5 also resulted in significantly (p <.05) lower respiratory compliance and greater microvascular permeability compared with sham animals. Following intestinal ischemia/reperfusion injury, PLV H-130 treated animals had significantly higher (p <.05) respiratory compliance than those treated with PLV PP-5 and a significantly lower (p <.05) intestinal ischemia/reperfusion-mediated increase in microvascular permeability than those treated with CMV or PLV PP-5. Thromboxane levels were significantly higher (p <.01) in injured animals treated with CMV or PLV PP-5 compared with comparably treated shams, were significantly lower (p <.01) in both PLV groups than CMV, and were further attenuated (p <.01) by PLV H-130 compared with PLV PP-5 animals. CONCLUSION We conclude that PLV with perfluorochemical liquids attenuates pulmonary sequelae resulting from remote organ injury and that the extent of lung protection depends on the physicochemical properties of the perfluorochemical liquids.
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Mammel MC. "Designer" perfluorocarbons and the lung. Crit Care Med 2002; 30:2395. [PMID: 12394983 DOI: 10.1097/00003246-200210000-00043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Sung FL, Zhu TY, Au-Yeung KKW, Siow YL, O K. Enhanced MCP-1 expression during ischemia/reperfusion injury is mediated by oxidative stress and NF-kappaB. Kidney Int 2002; 62:1160-70. [PMID: 12234286 DOI: 10.1111/j.1523-1755.2002.kid577.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Renal ischemia/reperfusion injury is a major cause of acute renal failure in both native kidneys and renal allografts. One important feature of such injury is monocyte/macrophage infiltration into the renal tissue. The infiltration of monocytes/macrophages can be induced by chemotactic factors produced by renal cells. Monocyte chemoattractant protein-1 (MCP-1) is a potent chemoattractant protein for monocyte recruitment. The objective of the present study was to investigate mechanisms of elevated MCP-1 expression in rat kidney during ischemia/reperfusion injury. METHODS The left kidney was subjected to one hour of ischemia followed by reperfusion for various time periods. The expression of MCP-1 mRNA was determined by nuclease protection assay and MCP-1 protein was identified by immunohistochemistry. Activation of a nuclear factor-kappa B (NF-kappaB) was determined by electrophoretic mobility shift assay and the level of lipid peroxides in the kidney was measured. RESULTS There was a significant increase in MCP-1 expression in the ischemia/reperfusion kidney 2 hours after reperfusion (210% of the control). This increase was accompanied by activation of NF-kappaB, suggesting that this transcription factor might be involved in the event. The number of monocytes was significantly elevated in the kidney 3 days after ischemia/reperfusion. Pretreatment of rats with NF-kappaB inhibitors not only prevented NF-kappaB activation induced by ischemia/reperfusion, but also inhibited MCP-1 mRNA expression. Further analysis revealed that oxidative stress and increased IkappaB-alpha phosphorylation might be an underlying mechanism for NF-kappaB activation and subsequent MCP-1 mRNA expression in the ischemia/reperfusion kidney. CONCLUSION The present study clearly demonstrates that enhanced MCP-1 expression in rat kidney during ischemia/reperfusion injury is mediated by NF-kappaB activation and oxidative stress. Elevated MCP-1 expression might be responsible for increased monocyte infiltration in the injured kidney.
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Mayevsky A, Barbiro-Michaely E, Ligeti L, MacLaughlin AC. Effects of euthanasia on brain physiological activities monitored in real-time. Neurol Res 2002; 24:647-51. [PMID: 12392199 DOI: 10.1179/016164102101200690] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Animal experimentation is terminated by the euthanasia procedure in order to avoid pain and minimize suffering. Very little is known about the real time physiological changes taking place in the brain of animals during the euthanasia. Since there is no way to evaluate the suffering of animals under euthanasia, it is assumed that objective physiological changes taking place could serve as a good way to compare various types of euthanasia procedures. In the present study we compared the effect of euthanasia induced by i. v. injection of concentrated KCL to that of Taxan T-61 (a standard mixture used by veterinarians). The responses of the cat brain were evaluated by monitoring the hemodynamic (CBF), metabolic (NADH redox state), electrical (EcoG) and extracellular ion levels, as an indicator to the ionic homeostasis.
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Abstract
UNLABELLED This paper aims to study the effect of ischemia-reperfusion on the post-rest inotropy and to characterize post-rest B1:B2 ratio as an index of intracellular Ca(2+) overload. When the rest interval between the cardiac beats is increased, the magnitude of the post-rest beats is increased. First beat (B1) is maximally potentiated with exponential decline of the second (B2) and subsequent beats, thereby establishing a normal B1:B2 ratio of post- rest inotropy of the cardiac muscle. The rest potentiation of B1 and subsequent decay in the magnitude B2 is thought to develop from the time-dependent changes in the Ca(2+)-uptake and release from the sarcoplasmic reticulum (SR). Ca(2+)-kinetics of SR can be modulated by a variety of interventions which produce Ca(2+) loading of the SR. METHODS Isolated perfused (K-H buffer, 34 degrees C) rat hearts were paced at 1 Hz (steady state frequency). Interbeat intervals between 1s and 10s were introduced and the recovery in the left ventricular contractile force (Pmax) of post-rest B1 and B2 for each interval was recorded. Their relative relationship was computed and compared under control and experimental conditions. RESULTS High extracellular Ca(2+) (2.50 to 7.0 mM) or low extracellular Na(+) (50% of control), and ischemia (60 min, 34 degrees C) - reperfusion (30 min, 34 degrees C) caused the reversal of the control relationship of the B1 to B2, with B2 being more potentiated than B1, accompanied by the appearance of after-contractions during the rest intervals of 4s or more. The mean (+/- SE) control B1:B2 ratio (at 4s interval) of 1.12 +/- 0.05 was significantly (P<0.001) reduced to 0.93 +/- 0.07; 0.89 +/- 0.01; and 0.96 +/- 0.02 after high Ca(2+) (6 mM) perfusion, low Na(+)(50%) perfusion and ischemia-reperfusion respectively. Simultaneous perfusion with ryanodine (1 microM) abolished the after-contractions and significantly increased the reduced ratios. The time course of changes in B1:B2 ratio after graded ischemia-reperfusion showed a significant fall in the ratio between 30 and 60 min of ischemia. A parallel change in Pmax and a significant rise in the left ventricular end-diastolic pressure, indicating an irreversible phase of the injury was recorded. No significant changes in B1:B2 ratio were detected during the reversible phase (<30 min) of the ischemia-reperfusion injury. CONCLUSIONS Ischemia-reperfusion induces significant alterations in the relative ratio of the post-rest contractions of the left ventricle in isolated perfused rat heart. The altered ratios were characterized to predict the irreversibility of the reperfusion injury and to index the extent of Ca(2+)-loading of the sarcoplasmic reticulum.
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Kanemoto Y, Nakase H, Akita N, Sakaki T. Effects of anti-intercellular adhesion molecule-1 antibody on reperfusion injury induced by late reperfusion in the rat middle cerebral artery occlusion model. Neurosurgery 2002; 51:1034-41; discussion 1041-2. [PMID: 12234414 DOI: 10.1097/00006123-200210000-00033] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2001] [Accepted: 03/06/2002] [Indexed: 01/16/2023] Open
Abstract
OBJECTIVE Inflammatory processes have been implicated in the mechanisms of reperfusion injury. The migration of leukocytes into ischemic tissue on reperfusion, which involves binding to the intercellular adhesion molecule (ICAM) of the endothelial cell, is thought to exacerbate tissue injury. The aim of the present study was to assess the effects of an anti-ICAM-1 antibody on reperfusion-induced injury after late reperfusion in a rat middle cerebral artery occlusion (MCAO) suture model. METHODS The animals were divided into four groups: 1) Group 1 (n = 7), 6 hours of permanent MCAO; 2) Group 2 (n = 7), 3 hours of MCAO followed by 3 hours of reperfusion; 3) Group 3 (n = 6), 6 hours of permanent MCAO and treatment with anti-ICAM-1 antibody (designated 1A29, 1 mg/kg) at 2 hours after onset of MCAO; and 4) Group 4 (n = 6), 3 hours of MCAO followed by 3 hours of reperfusion and 1A29 treatment. During the experiment, regional cerebral blood flow was measured by a laser Doppler flowmetric scanning technique. At the 6-hour time point, all rats were killed, and the results of leukocyte infiltration by myeloperoxidase activity and histological analysis using 2,3,5-triphenyltetrazolium chloride staining were examined. RESULTS Regional cerebral blood flow values before and after MCAO were not significantly different among the four groups. Regional cerebral blood flow values after reperfusion were not significantly different in the two reperfused groups. The percentage brain injury volumes in both the total and cortical areas and the myeloperoxidase activity in the latter were significantly larger in Group 2 (the reperfused group) than in the other groups (P < 0.05) but were decreased by anti-ICAM-1 antibody treatment (Group 2 versus Group 4, P < 0.05). However, there were no differences between Groups 1 and 3 without reperfusion. Myeloperoxidase activities correlated positively with infarct volumes (P < 0.01). CONCLUSION The findings of this study demonstrate that the anti-ICAM antibody treatment is effective at inhibiting early inflammatory processes and reperfusion-induced injury caused by late arterial recanalization, which would contribute to widening the therapeutic window of thrombolytic therapy.
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Temsah RM, Netticadan T, Kawabata KI, Dhalla NS. Lack of both oxygen and glucose contributes to I/R-induced changes in cardiac SR function. Am J Physiol Cell Physiol 2002; 283:C1306-12. [PMID: 12225993 DOI: 10.1152/ajpcell.00138.2002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although ischemia-reperfusion (I/R) has been shown to depress cardiac performance and sarcoplasmic reticulum (SR) function, the mechanisms underlying these alterations are poorly understood. Because lack of oxygen and substrate deprivation are known to occur during the ischemic phase, we examined the effects of reperfusion on cardiac performance and SR function in hearts subjected to hypoxia and substrate lack. For this purpose, isolated rat hearts were perfused with hypoxic and/or glucose-free medium for 30 min and then reperfused with normal medium for 1 h; the SR vesicles were isolated for studying the Ca(2+)-transport activities. Reperfusion with normal medium of hearts deprived of oxygen or glucose showed no changes in cardiac performance and SR function. However, reperfusion of hearts perfused with hypoxic glucose-free medium showed ~45% decrease in cardiac contractile activities as well as 23 and 64% reduction in SR Ca(2+)-uptake and Ca(2+)-release activities, respectively, without any change in the level of SR Ca(2+)-cycling proteins. Depressed SR function in these hearts was associated with a reduction in Ca(2+)/calmodulin-dependent protein kinase (CaMK) phosphorylation of the SR Ca(2+)-cycling proteins and 34% decrease in SR CaMK activity. These changes in cardiac performance, SR function, and SR CaMK activity in the hypoxic, glucose-deprived, reperfused hearts were similar to those observed in hearts subjected to 30 min of global ischemia and 60 min of reperfusion. The results therefore suggest that the lack of both oxygen and substrate during the ischemic phase may contribute to the I/R-induced alterations in cardiac performance and SR function. Furthermore, these abnormalities were associated with reduced SR CaMK activity.
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Kloss CUA, Thomassen N, Fesl G, Martens KH, Yousri TA, Hamann GF. Tissue-saving infarct volumetry using histochemistry validated by MRI in rat focal ischemia. Neurol Res 2002; 24:713-8. [PMID: 12392211 DOI: 10.1179/016164102101200636] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Lesion size is an important outcome parameter in experimental stroke research. However, most methods of measuring the infarct volume in rodents either require expensive equipment or render the brain tissue unusable for further analysis. We report on an inexpensive, tissue-saving method for quantifying the infarct volume in small rodents. After 3 h of middle cerebral artery occlusion (MCAO) and 24 h of reperfusion in male Wistar rats, the lesion was first identified using MRI with T2-weighted sequences. The infarct was then visualized in unfixed brain cryosections using microtubule associated protein 2 (MAP2)-immunohistochemistry and silver infarct staining. The lesion areas detected by all three different methods completely overlapped. The infarct volume was calculated for each method from the lesion area size on serial sections and the distance between them. Significant differences in lesion size were found between the individual animals (p = 0.000056), but not between different methods (p > 0.05). MAP2 immunohistochemistry is a convenient and valid method to measure stroke lesion volume; in addition 98% of the brain tissue is saved and available for use in further histological, immunohistochemical, and biochemical analysis.
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Abstract
Interactions between the immune system and skeletal muscle may play a significant role in modulating the course of muscle injury and repair after modified musculoskeletal loading. Current evidence indicates that activation of the complement system is an early event during modified loading, which then leads to inflammatory cell invasion. However, the functions of those inflammatory cells are complex and they seem to be capable of promoting additional injury and repair. Recent findings implicate an early invading neutrophil population in increasing muscle damage that is detected by the presence of muscle membrane lesions. Macrophages that invade subsequently serve to remove cellular debris, and seem to promote repair. However, macrophages also have the ability to increase damage in muscle in which there is an impaired capacity to generate nitric oxide. In vivo and in vitro evidence indicates that muscle-derived nitric oxide can serve an important role in protecting muscle from membrane damage by invading inflammatory cells. Collectively, these findings indicate that the dynamic balance between inflammatory cells, the complement system, and muscle-derived free radicals can play important roles in the secondary damage of muscle during modified musculoskeletal loading.
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Zhang X, Bedard EL, Potter R, Zhong R, Alam J, Choi AMK, Lee PJ. Mitogen-activated protein kinases regulate HO-1 gene transcription after ischemia-reperfusion lung injury. Am J Physiol Lung Cell Mol Physiol 2002; 283:L815-29. [PMID: 12225959 DOI: 10.1152/ajplung.00485.2001] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Lung ischemia-reperfusion (I-R) is an important model of oxidant-mediated acute lung and vascular injury. Heme oxygenase-1 (HO-1) is a cytoprotective gene that is markedly induced by lung I-R injury. HO-1 mRNA is increased in mouse lung after 30 min of lung hilar clamping (ischemia) followed by 2-6 h of unclamping (reperfusion) compared with control mice. In a variety of vascular cell types, HO-1 mRNA is induced after 24 h of anoxia followed by 30 min-1 h of reoxygenation (A-R). Transfection studies reveal that the promoter and 5'-distal enhancer E1 are necessary and sufficient for increased HO-1 gene transcription after A-R. Immunoblotting studies show all three subfamilies of MAPKs (ERK, JNK, and p38) are activated by 15 min of reperfusion. We also demonstrate that HO-1 gene transcription after A-R involves ERK, JNK, and p38 MAPK pathways. Together, our data show that I-R not only induces HO-1 gene expression in mouse lungs and vascular cells but that gene transcription occurs via the promoter and E1 enhancer and involves upstream MAPK pathways.
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MESH Headings
- Animals
- Aorta/cytology
- Cells, Cultured
- Enhancer Elements, Genetic/physiology
- Enzyme Inhibitors/pharmacology
- Flavonoids/pharmacology
- Gene Expression Regulation, Enzymologic/physiology
- Heme Oxygenase (Decyclizing)/analysis
- Heme Oxygenase (Decyclizing)/genetics
- Heme Oxygenase-1
- Imidazoles/pharmacology
- Lung Diseases/metabolism
- Lung Diseases/physiopathology
- MAP Kinase Signaling System/physiology
- Membrane Proteins
- Mice
- Mitogen-Activated Protein Kinase 9
- Mitogen-Activated Protein Kinases/antagonists & inhibitors
- Mitogen-Activated Protein Kinases/genetics
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/enzymology
- Mutagenesis/physiology
- Promoter Regions, Genetic/physiology
- Pulmonary Artery/cytology
- Pyridines/pharmacology
- RNA, Messenger/analysis
- Rats
- Reperfusion Injury/metabolism
- Reperfusion Injury/physiopathology
- Transcription, Genetic/physiology
- p38 Mitogen-Activated Protein Kinases
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Wang X, Niwa M, Hara A, Matsuno H, Kawase K, Kozawa O, Mow H, Uematsu T. Neuronal degradation in mouse retina after a transient ischemia and protective effect of hypothermia. Neurol Res 2002; 24:730-5. [PMID: 12392214 DOI: 10.1179/016164102101200663] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Temporal profile of neuronal deaths in the mouse retina evoked by a transient retinal ischemia and the protective effect of hypothermia on such deaths were evaluated. A transient ischemic insult was induced in the mouse retina by elevating the intra-ocular pressure. The retina tissue responses after reperfusion were histopathologically detected by monitoring the retinal cell death in the ganglion cell layer and inner nuclear layer, using a sequential TUNEL-staining technique, and by measuring the inner retinal thickness. Elevation of intra-ocular pressure induced a time-related appearance of TUNEL-positive cells in the mouse inner retinas. Peak TUNEL staining occurred 12 h after reperfusion. Lowering mice body temperature to 35 degrees C, 33 degrees C and 29 degrees C during the ischemia period significantly inhibited DNA fragmentation of retinal neurons in a lowering temperature dependent manner. In this experiment, the inner retinal thickness was preserved in 29 degrees C group compared with that in 37 degrees C group. From these results, the 45-min transient ischemia and histopathological examination 12 h later provided a reproducible number of retinal neuronal deaths. Furthermore, hypothermic intervention showed a protective effect to salvage retinal neuronal cells from a transient ischemic insult.
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