异氟醚对离体大鼠心肌缺血/再灌注损伤的影响

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。

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

Aim To investigate the effects of Isofluraneon function,metabolism,ATPase activity and free radicals in isolated ischemia /reperfusion(I/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 Ca2+-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 unchanged.The myocardial ATP content decreased slowly in isoflurane group.At the end of reperfusion,ventricular function,CF,myocardial ATP content and the activity of Ca2+-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 myocardium,improve the recovery of function and metabolism,and increase CF and the activity of Ca2+-ATPase and Na+,K+-ATPase.