异氟醚对离体大鼠心肌缺血/再灌注损伤的影响

Effects of volatile isoflurane on rat heart ischemia-reperfusion injury in vitro

目的研究麻醉药异氟醚对缺血/再灌注心肌功能和代谢、氧自由基及ATP酶活性的影响。方法SD大鼠56只,随机分为7小组,每组8只。采用Langendorff离体大鼠心脏模型。按给药方式又分为两大组,各组记录平衡后,给药后(或续灌15min)复灌末左室收缩压(LVSP)、左室舒张末期压(LVEDP)、左室发展压(LVDP)、左室压力升高或降低最大速率(±dp/dtmax)、心率(HR)、冠脉流量(CF)。实验结束后测定心肌超氧化物歧化酶(SOD)活性、心肌丙二醛(MDA)含量、高能磷酸盐(ATP)含量、Na+,K+-ATP酶、Ca2+-ATP酶活性。结果异氟醚组明显降低LVDP、+dp/dt,升高LVEDP(P<0.05);缺血/再灌注后,异氟醚组的LVDP分别恢复到基础值的57%、61%、59%、77%,+dp/dt分别恢复到基础值的45%、50%、46%、52%;与再灌末对照组相比,差异具有显著性;异氟醚组能提高心肌ATP含量,缺血后心肌ATP下降较慢,复灌后恢复较快;复灌后异氟醚组SOD活性较高,MDA生成量下降(P<0.05);异氟醚能提高再灌后心肌Na+,K+-ATP酶活性(P<0.05)。结论异氟醚对心肌收缩功能和Ca2+-ATP酶活性具有一定的抑制作用,能明显促进心肌功能与代谢的恢复,提高冠脉流量、心肌Ca2+-ATP酶及Na+,K+-ATP酶活性。

Aim To investigate the effects of Isofluraneon function, metabolism, ATPase activity and free radicals in isolated ischemia /reperfusion （ L/R ） rat hearts. Methods 56 SD rats were randomly divided into 7 small groups （n = 7 ）, or 2 big groups according to given drug. In a normal thermal isolated Langendorff rat heart model, Myocardial Adenosine triphosphate （ ATP ） , Malodialdehyde （ MDA ） , Activity of Ca^2＋ -ATPase, Na^＋, K ^＋-ATPase and Superoxide Dismutase （SOD） were determined. Results In isoflurane group, LVDP and dp/dt decreased, CF and ATP increased while the activity of Na^＋, K^＋ -ATPase remained un- changed. The myocardial ATP content decreased slowly in isoflurane group. At the end of reperfusion, ventricular function, CF, myocardial ATP content and the activity of Ca^2＋ -ATPase and SOD in isoflurane group were significantly higher while myocardial MDA was significantly lower than those in control group. Conclusion Isoflurane can depress myocardial systolic function and activity of Ca^＋ -ATPase in normal myocardiurn, improve the recovery of function and metabolism, and increase CF and the activity of Ca^2＋-ATPase and Na^＋, K^＋ -ATPase.