镁对缺血后再灌注心肌线粒体的影响

大鼠等容心脏制备经低血流缺血６０ｍｉｎ后复灌３０ｍｉｎ。组（２）灌注液中镁浓度始终为１．２ｍｍｏｌ／Ｌ，而组（３）及组（１）则于缺血期分别换用１５ｍｍｏｌ／Ｌ或无镁灌注淮。结果表明，高镁对心肌线粒体Ｃａ＾２＋－ＡＴＰ酶活性，合成ＡＴＰ能力具明显保护作用，并减轻了钙超载现象，部分地防止缺血后再灌注损伤。

EFFECT OF MAGNESIUM ON POSTISCHEMIC REPERFUSED MYOCARDIAL MITOCHONDRIA

Isovolumic rat heart preparations were exposed to low flow ischemia (0. 2 ml/ min) for 60 min, followed by 30 min of reperfusion. The concentration of Mg(2 ) was maintained 1. 2 mmol/L throughout the study in group 2, while increased to 15 mmol/ L or depleted to zero during ischemia only in group 3 and group 1 respectively. High concentration Mg(2 ) showed a significantly protective effect on Ca-ATPase activity and synthesis ability of ATP in myocardial mitochondria, and decreased its calcium overload. Thus it appears that high concentration Mg(2 )infusion may partially reverse positschemicreperfusion injury to heart.