Berlet H H, Bonsmann I, Birringer H
Biochim Biophys Acta. 1976 Jun 23;437(1):166-74. doi: 10.1016/0304-4165(76)90358-5.
We evaluated brown and white adipose tissues for the presence of creatine, phosphocreatine and creatine phosphokinase activity. In rats 3.6 and 0.4 mumol of total creatine were found per g wet weight of brown and white adipose tissues, respectively. We were able to identify creatine by thin-layer chromatography after a pulse label of [14C]creatine had been given in vivo. Free creatine and phosphocreatine were shown to occur by column chromatography. Of the total creatine of brown adipose tissue, approximately one third to one half were attributable to phosphocreatine. The activity of creatine phosphokinase was demonstrated in both white and brown adipose tissue, the values of the latter prevailing over those of the former by a factor of 200, if based on wet weight, or 50, if expressed as specific enzyme activity. The labeling of total creatine in vivo proceeded much faster in adipose tissue than in skeletal muscle. The results strongly suggest that the energy metabolism of adipose tissue is closely dependent on the presence of creatine. The specific activities of free creatine and phosphocreatine of brown adipose tissue differed strikingly as long as 24 h after radioactive creatine was injected; this difference points to a metabolic or structural compartmentation of creatine.
我们评估了棕色和白色脂肪组织中肌酸、磷酸肌酸和肌酸磷酸激酶的活性。在大鼠中，每克湿重的棕色和白色脂肪组织中分别发现了3.6和0.4微摩尔的总肌酸。在体内给予[14C]肌酸脉冲标记后，我们能够通过薄层色谱法鉴定肌酸。通过柱色谱法显示存在游离肌酸和磷酸肌酸。棕色脂肪组织的总肌酸中，约三分之一至二分之一归因于磷酸肌酸。白色和棕色脂肪组织中均证实有肌酸磷酸激酶的活性，如果以湿重为基础，后者的值比前者高200倍；如果以比酶活性表示，则高50倍。体内总肌酸的标记在脂肪组织中比在骨骼肌中进行得快得多。结果强烈表明，脂肪组织的能量代谢紧密依赖于肌酸的存在。注射放射性肌酸后长达24小时，棕色脂肪组织中游离肌酸和磷酸肌酸的比活性显著不同；这种差异表明肌酸存在代谢或结构分隔。
