Maoz Daniel, Lee Ho-Joo, Deutsch Joseph, Rapoport Stanley I, Bazinet Richard P
Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, Maryland 20892, USA.
Lipids. 2005 Nov;40(11):1149-54. doi: 10.1007/s11745-005-1479-9.
Tissues changes in FA metabolism can occur quite rapidly in response to ischemia and may require immediate microwave fixation to determine basal concentrations. The present study aimed to quantify the effects of immediate no-flow ischemia on concentrations of individual nonesterified FA (NEFA) and acyl-CoA species in the rat heart. Male CDF 344 rats were anesthetized and decapitated either 5 min prior to being microwaved (5.5 kW, 3.4 s, twice) to produce ischemia or microwaved prior to decapitation (nonischemic). Hearts were then removed and used to measure the concentrations of acyl-CoA species and FA in several lipid classes. The ischemic heart total NEFA concentration was significantly lower than that in the nonischemic heart (11.9 vs. 19.0 nmol/g). Several individual NEFA concentrations were decreased by 31-85%. Ischemic heart total long-chain acyl-CoA concentrations (21.0 nmol/g) were significantly higher than those in nonischemic hearts (11.4 nmol/g). Increased concentrations of individual acyl-CoA species occurred in palmitoyl-CoA, stearoyl-CoA, oleoyl-CoA, and linoleoyl-CoA. Concentrations of short-chain acetyl-CoA and beta-hydroxy-beta-methylglutaryl-CoA were also two- to three-fold higher in ischemic hearts than in nonischemic hearts. The FA concentration in TG and phospholipids generally did not differ between the groups. Decreases in concentrations of individual FA and increases in acyl-CoA species during no-flow ischemia occur very rapidly within the heart. Although it is not clear how these alterations contribute to the pathogenesis of ischemia, it is evident that future studies attempting to quantify basal levels of these metabolites could use microwave fixation.
脂肪酸代谢中的组织变化可因缺血而迅速发生，可能需要立即进行微波固定以确定基础浓度。本研究旨在量化即刻无血流缺血对大鼠心脏中各个非酯化脂肪酸（NEFA）和酰基辅酶A种类浓度的影响。雄性CDF 344大鼠在进行微波处理（5.5千瓦，3.4秒，两次）以产生缺血前5分钟或在断头前进行微波处理（非缺血）时被麻醉并断头。然后取出心脏，用于测量几种脂质类别中酰基辅酶A种类和脂肪酸的浓度。缺血心脏的总NEFA浓度显著低于非缺血心脏（11.9对19.0纳摩尔/克）。几种个体NEFA浓度降低了31 - 85%。缺血心脏的总长链酰基辅酶A浓度（21.0纳摩尔/克）显著高于非缺血心脏（11.4纳摩尔/克）。棕榈酰辅酶A、硬脂酰辅酶A、油酰辅酶A和亚油酰辅酶A中个体酰基辅酶A种类的浓度增加。缺血心脏中短链乙酰辅酶A和β-羟基-β-甲基戊二酰辅酶A的浓度也比非缺血心脏高两到三倍。甘油三酯和磷脂中的脂肪酸浓度在两组之间一般没有差异。在无血流缺血期间，心脏内个体脂肪酸浓度的降低和酰基辅酶A种类的增加非常迅速。虽然尚不清楚这些改变如何促成缺血的发病机制，但很明显，未来试图量化这些代谢物基础水平的研究可以使用微波固定。
