Fujisawa S, Kobayashi A, Hironaka Y, Yamazaki N
Third Department of Internal Medicine, Hamamatsu University School of Medicine, Japan.
Jpn Heart J. 1992 Sep;33(5):693-705. doi: 10.1536/ihj.33.693.
The purpose of this study was to investigate the cellular distribution of carnitine and its acyl derivatives in the normal and ischemic myocardium, and the effects of exogenous 1-carnitine on this distribution and mitochondrial function in the ischemic dog heart. Under non-ischemic conditions, about 93% of the total cellular carnitine was located in the cytosolic compartment and 6.5% in the mitochondrial compartment. Sixty minutes of ischemia induced a decrease in the cytosolic free carnitine content, but caused the accumulation of long-chain acylcarnitine in the cytosolic and mitochondrial compartments. Treatment with 1-carnitine (30 or 100 mg/kg, i.v.) inhibited the mitochondrial accumulation of long-chain acylcarnitine. Free fatty acid (FFA) metabolism in the mitochondria differs from that in the cytosol. So, it is necessary to investigate the changes in FFA metabolism in both of these cellular compartments. Our results suggest that 1-carnitine has a protective effect on the ischemic heart by selectively reducing mitochondrial accumulation of long-chain acylcarnitine.
本研究的目的是调查肉碱及其酰基衍生物在正常心肌和缺血心肌中的细胞分布，以及外源性左旋肉碱对缺血犬心脏中这种分布和线粒体功能的影响。在非缺血条件下，细胞内总肉碱的约93%位于胞质部分，6.5%位于线粒体部分。60分钟的缺血导致胞质游离肉碱含量降低，但导致长链酰基肉碱在胞质和线粒体部分积累。用左旋肉碱（30或100mg/kg，静脉注射）治疗可抑制长链酰基肉碱在线粒体中的积累。线粒体中的游离脂肪酸（FFA）代谢与胞质中的不同。因此，有必要研究这两个细胞部分中FFA代谢的变化。我们的结果表明，左旋肉碱通过选择性减少长链酰基肉碱在线粒体中的积累，对缺血心脏具有保护作用。
