Dogan Mustafa, Peker Recep O, Donmez Soner, Gokalp Osman
Diabetes Research Group, King's College, London, UK.
Interact Cardiovasc Thorac Surg. 2012 Jul;15(1):1-4. doi: 10.1093/icvts/ivs051. Epub 2012 Apr 21.
Perioperative vasospasm during cardiovascular surgery is a challenging problem. Several vasodilator agents are frequently utilized for its prevention in surgical practice. Magnesium and diltiazem both have known potential vasorelaxant effects. We planned to compare the efficacy of diltiazem and magnesium in relieving phenylephrine-precontracted rat aortic rings. Ten young adult female Wistar albino rats weighing 230-260 g were used in this study. The aortic rings in the organ bath equilibrated and reached their baseline tension. Precontraction was induced by 0.001 mmol/l phenylephrine and cumulative concentration-relaxation curves were obtained by consecutively increasing the addition of either diltiazem (10(-6)-0.1 mmol/l) or magnesium (0.1-10 mmol/l). The mean maximal relaxation responses observed by diltiazem and magnesium on separate aortic rings were 90 ± 3 and 53 ± 2%, respectively. The calculated EC50 of diltiazem was 0.01035 mmol/l, whereas the EC50 of magnesium was 4.064 mmol/l (P < 0.05). Both magnesium and diltiazem produced vasorelaxation on phenylephrine-precontracted rat aortic rings in this study, but the potency of diltiazem regarding the EC50 value was significantly higher than that of magnesium. Magnesium could be a candidate together with diltiazem to inhibit vasospasm on arterial grafts during coronary bypass surgery.
心血管手术期间的围手术期血管痉挛是一个具有挑战性的问题。在外科实践中，几种血管扩张剂经常被用于预防血管痉挛。镁和地尔硫䓬都具有已知的潜在血管舒张作用。我们计划比较地尔硫䓬和镁在缓解去氧肾上腺素预收缩的大鼠主动脉环方面的疗效。本研究使用了10只体重230 - 260克的成年雌性Wistar白化大鼠。将主动脉环置于器官浴中平衡并达到其基线张力。用0.001 mmol/L去氧肾上腺素诱导预收缩，并通过连续增加地尔硫䓬（10(-6)-0.1 mmol/L）或镁（0.1 - 10 mmol/L）的添加量来获得累积浓度 - 舒张曲线。地尔硫䓬和镁在单独的主动脉环上观察到的平均最大舒张反应分别为90±3%和53±2%。计算得出地尔硫䓬的EC50为0.01035 mmol/L，而镁的EC50为4.064 mmol/L（P < 0.05）。在本研究中，镁和地尔硫䓬均能使去氧肾上腺素预收缩的大鼠主动脉环产生血管舒张，但就EC50值而言，地尔硫䓬的效力明显高于镁。在冠状动脉搭桥手术期间，镁可以与地尔硫䓬一起作为抑制动脉移植物血管痉挛的候选药物。
