Effects of ropivacaine and bupivacaine on energy supply and mitochondrial oxidation of isolated rabbit heart muscle / 中华麻醉学杂志

ABSTRACT

Objective The purpose of this study was to investigate the effects of ropivacaine and bupivacaine on energy supply and mitochondrial oxidation phosphorylation of isolated rabbit heart muscle in order to compare the cardiotoxicity of the two local anestheties and explain the mechanism Methods Twenty four New Zealand rabbits weighing (2135?345)g were randomly divided into three groups of 8 animals each: control group(C); ropivacaine group(R) and bupivacaine group (B) The animals were anesthetized with intraperitoneal urethane 2g?kg -1 and heparinized (heparin 4mg?kg -1 ) Heart was quickly removed and connected to Langendoff preparation and perfused with oxygenated Krebs Henseleit buffer solution at normothermia(37℃) via aorta After 15 min perfusion, ropivacaine (group R) or bupivacaine(group B) was added to perfusate(500ng?ml -1 ) The heart was then perfused for another 10 min Myocardial tissue was taken from ventricle for determination of ATP, ADP and AMP content with high performance liquid chromatography Myocardial mitochondria was prepared and its oxidation of pyruvate and palmitoylcarnitine was measured using Clark electrode Results Myocardial ATP and ADP decreased significantly in group R and B as compared with those in group C The decrease in ATP and ADP in group B was more than that in group R (P