Background Both ischemic preconditioning (IPC) and limb remote ischemic postconditioning (LRIPOC) have been shown to possess significantly different cardioprotective effects against the myocardial ischemia reperfu...Background Both ischemic preconditioning (IPC) and limb remote ischemic postconditioning (LRIPOC) have been shown to possess significantly different cardioprotective effects against the myocardial ischemia reperfusion injury (IRI), but no study has compared the anti-inflammatory effects of IPC and LRIPOC during myocardial IRI process. We hypothesized that IPC and LRIPOC would produce different anti-inflammatory effects in an in vivo rat model with myocardial IRI.展开更多
Background This study aimed at assessing the effect of noninvasive limb preconditioning on myocardial infarct size, and determining whether nitric oxide and neurogenic pathway play an important role in the mechanism o...Background This study aimed at assessing the effect of noninvasive limb preconditioning on myocardial infarct size, and determining whether nitric oxide and neurogenic pathway play an important role in the mechanism of acute remote ischemic preconditioning (IPC).Methods Forty Wistar rats were randomly divided into four experimental groups. In Group I , the rats underwent 30-minute occlusion of the left anterior descending coronary artery, and 120-minute reperfusion. In Group PL, the rats underwent four cycles of 5-minute occlusion and reperfusion of both hind limbs using a tourniquet before the experiment was continued as in Group I. In Group PL-N and Group PL-,, we administered L-nitro-arginine methyl ester (L-NAME) 10 mg/kg or hexamethonium chloride 20 mg,/kg intravenously, 10 minutes before IPC. Infarct size as a percentage of the area at risk was determined by triphenyhetrazolium chloride staining.Results There were no statistically significant differences in mean arterial pressure and heart rate among these groups at any time point during the experiment ( P〉0. 05 ). The myocardial infarct size (IS) was decreased significantly in Group PL and Group PL-U compared with Group I , and the IS/AAR was 34. 5%± 7.6%, 35.9%±8.6% and58.5%±8.5%, respectively (P〈0.05). The IS/AAR was 49.1%±6.5% in Group PEN, and there was no significant difference compared with Group I (P〉0. 05 ).Conclusions Noninvasive limb IPC is effective in protecting the myocardium from ischemia reperfusion injury. Nitric oxide plays an important role in the mechanism of acute remote IPC, in which the neurogenic pathway is not involved.展开更多
Objective To investigate the effect of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) on limb ischemia/reperfusion injury of rats and the mechanism Methods The hind limb ische...Objective To investigate the effect of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) on limb ischemia/reperfusion injury of rats and the mechanism Methods The hind limb ischemia/reperfusion injury of male SD rats was induced by tourniquet for 2 hours and then reperfusing for 12 hours with administration of different agents Animals were divided into control, bFGF 10 and bFGF 50, VEGF 10 and VEGF 50 group by infusing physiological saline, 10 and 50?μg/kg bFGE, 10 and 50?μg/kg VEGF, respectively Blood was collected to determine malonyldialdehyde (MDA), and the ischemic reperfused gastrocnemius muscle and the contralateral control one were harvested together for measurement of tissue viability, water content, myeloperoxidose (MPO) activity, ATP and MDA concentration Results Compared with control group, tissue viability of ischemia/reperfusion limb in bFGF 10 and bFGF 50 group increased by 16 0% ( P <0 05) and 32 8% ( P <0 01), ATP content increased by 14 8% and 35 6% ( P <0 01), and plasma MDA level decreased by 45 2% and 56 2% ( P <0 01) 10?μg/kg bFGF had no significant effect on tissue water content, MPO activity, MDA concentration of ischemia/reperfusion limb, while 50?μg/kg of bFGF lowered these values by 15 7%, 32 5% and 13 6% ( P <0 05) and 14 7% ( P <0 01), MPO activity augmented by 44 9% and 96 1% ( P <0 01), ATP content decreased by 13 1% ( P <0 05) and 33 3% ( P <0 01) Plasma and tissue MDA concentrations in VEGF 10 group had no significant changes ( P >0 05), while in VEGF 50 group, these values were elevated by 46 4% and 38 6% ( P <0 01) Conclusion bFGF attenuated, while VEGF exacerbated ischemia/reperfusion injury of rat limb significantly, the mechanism of which was probably related to preventing or enhancing lipid peroxide, and increasing or decreasing energy store展开更多
文摘Background Both ischemic preconditioning (IPC) and limb remote ischemic postconditioning (LRIPOC) have been shown to possess significantly different cardioprotective effects against the myocardial ischemia reperfusion injury (IRI), but no study has compared the anti-inflammatory effects of IPC and LRIPOC during myocardial IRI process. We hypothesized that IPC and LRIPOC would produce different anti-inflammatory effects in an in vivo rat model with myocardial IRI.
基金This study was supported by a grant from the Natural ScienceFoundation of Liaoning Education Committee (No.2004D193).
文摘Background This study aimed at assessing the effect of noninvasive limb preconditioning on myocardial infarct size, and determining whether nitric oxide and neurogenic pathway play an important role in the mechanism of acute remote ischemic preconditioning (IPC).Methods Forty Wistar rats were randomly divided into four experimental groups. In Group I , the rats underwent 30-minute occlusion of the left anterior descending coronary artery, and 120-minute reperfusion. In Group PL, the rats underwent four cycles of 5-minute occlusion and reperfusion of both hind limbs using a tourniquet before the experiment was continued as in Group I. In Group PL-N and Group PL-,, we administered L-nitro-arginine methyl ester (L-NAME) 10 mg/kg or hexamethonium chloride 20 mg,/kg intravenously, 10 minutes before IPC. Infarct size as a percentage of the area at risk was determined by triphenyhetrazolium chloride staining.Results There were no statistically significant differences in mean arterial pressure and heart rate among these groups at any time point during the experiment ( P〉0. 05 ). The myocardial infarct size (IS) was decreased significantly in Group PL and Group PL-U compared with Group I , and the IS/AAR was 34. 5%± 7.6%, 35.9%±8.6% and58.5%±8.5%, respectively (P〈0.05). The IS/AAR was 49.1%±6.5% in Group PEN, and there was no significant difference compared with Group I (P〉0. 05 ).Conclusions Noninvasive limb IPC is effective in protecting the myocardium from ischemia reperfusion injury. Nitric oxide plays an important role in the mechanism of acute remote IPC, in which the neurogenic pathway is not involved.
文摘Objective To investigate the effect of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) on limb ischemia/reperfusion injury of rats and the mechanism Methods The hind limb ischemia/reperfusion injury of male SD rats was induced by tourniquet for 2 hours and then reperfusing for 12 hours with administration of different agents Animals were divided into control, bFGF 10 and bFGF 50, VEGF 10 and VEGF 50 group by infusing physiological saline, 10 and 50?μg/kg bFGE, 10 and 50?μg/kg VEGF, respectively Blood was collected to determine malonyldialdehyde (MDA), and the ischemic reperfused gastrocnemius muscle and the contralateral control one were harvested together for measurement of tissue viability, water content, myeloperoxidose (MPO) activity, ATP and MDA concentration Results Compared with control group, tissue viability of ischemia/reperfusion limb in bFGF 10 and bFGF 50 group increased by 16 0% ( P <0 05) and 32 8% ( P <0 01), ATP content increased by 14 8% and 35 6% ( P <0 01), and plasma MDA level decreased by 45 2% and 56 2% ( P <0 01) 10?μg/kg bFGF had no significant effect on tissue water content, MPO activity, MDA concentration of ischemia/reperfusion limb, while 50?μg/kg of bFGF lowered these values by 15 7%, 32 5% and 13 6% ( P <0 05) and 14 7% ( P <0 01), MPO activity augmented by 44 9% and 96 1% ( P <0 01), ATP content decreased by 13 1% ( P <0 05) and 33 3% ( P <0 01) Plasma and tissue MDA concentrations in VEGF 10 group had no significant changes ( P >0 05), while in VEGF 50 group, these values were elevated by 46 4% and 38 6% ( P <0 01) Conclusion bFGF attenuated, while VEGF exacerbated ischemia/reperfusion injury of rat limb significantly, the mechanism of which was probably related to preventing or enhancing lipid peroxide, and increasing or decreasing energy store