不同镁给药时间对梗死面积影响的比较。

Comparison of the effects of different magnesium administration times on infarct size.

作者信息

Martínez Demaría Diego R, Cingolani Horacio E, Mosca Susana M

机构信息

Fellow in Cardiology, Residencia Hospitalaria Universitaria del Hospital Italiano de La Plata, La Plata; and.

出版信息

Exp Clin Cardiol. 2003 Spring;8(1):17-20.

PMID:19644582

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC2716194/

Abstract

BACKGROUND

The protection of high magnesium on infarct size remains controversial.

OBJECTIVE

To examine the effects of magnesium administered before ischemia or early in reperfusion on infarct size in a rat model of global ischemia

METHODS

Isolated rat hearts were submitted to 40 min of normothermic global ischemia and 2 h of reperfusion. After 20 min of stabilization, four protocols were performed: ischemic control (IC) hearts; 15 mM of magnesium chloride administered 15 min before ischemia (MgI); 15 mM of magnesium chloride administered during the first 15 min of reperfusion (MgR); or 15 mM magnesium plus 5 mM calcium (Mg+Ca) before ischemia. Infarct size was measured by triphenyltetrazolium staining. Contractile function was assessed by left ventricular developed pressure and the maximal velocity of rise of left ventricular presssure.

RESULTS

The infarct size in IC hearts was 44+/-5%. In MgI and MgR hearts, the infarct diminished to 4.5+/-1.5% and 18+/-4%, respectively. In Mg+Ca hearts, the protection was also obtained (19+/-3%). Myocardial function also improved significantly by magnesium treatment. At the end of reperfusion, left ventricular developed pressure and maximal velocity of rise of left ventricular pressure values were 23+/-6% and 22+/-3% in MgI; and 10+/-3% and 9+/-2.6% in MgR versus 2+/-0.7% and 2.3+/-0.8% in IC hearts, respectively.

CONCLUSION

The treatment with magnesium either before ischemia or early in reperfusion has an infarct size limiting effect in a model of global ischemia. This protective effect is partially due to its calcium antagonistic action.

摘要

背景

高镁对梗死面积的保护作用仍存在争议。

目的

在大鼠全脑缺血模型中，研究缺血前或再灌注早期给予镁对梗死面积的影响。

方法

将离体大鼠心脏进行40分钟常温全脑缺血及2小时再灌注。稳定20分钟后，进行四个方案：缺血对照组（IC）心脏；缺血前15分钟给予15 mM氯化镁（MgI）；再灌注最初15分钟给予15 mM氯化镁（MgR）；或缺血前给予15 mM镁加5 mM钙（Mg+Ca）。通过三苯基四氮唑染色测量梗死面积。通过左心室舒张末压和左心室压力上升最大速度评估收缩功能。

结果

IC组心脏梗死面积为44±5%。MgI组和MgR组心脏梗死面积分别降至4.5±1.5%和18±4%。Mg+Ca组心脏也获得了保护（19±3%）。镁治疗还显著改善了心肌功能。再灌注结束时，MgI组左心室舒张末压和左心室压力上升最大速度值分别为23±6%和22±3%；MgR组为10±3%和9±2.6%，而IC组心脏分别为2±0.7%和2.3±0.8%。