Saggerson E D, Carpenter C A
Biochem J. 1986 May 15;236(1):137-41. doi: 10.1042/bj2360137.
Mitochondria were isolated from rat adult liver, foetal liver, kidney cortex, heart, skeletal muscle and interscapular brown adipose tissue. DL-2-Bromopalmitoyl-CoA inhibited the overt form of carnitine palmitoyltransferase (CPT1) in heart, skeletal muscle and brown adipose tissue, with an IC50 value (concentration giving 50% inhibition) of 1.3-1.6 microM. By contrast, the IC50 value for inhibition of the kidney or adult liver enzyme was 0.08-0.1 microM. CPT1 in near-term foetal liver differed from that in adult liver in that the IC50 for inhibition by 2-bromopalmitoyl-CoA was 0.57 microM. It is suggested that there may be tissue-specific forms of the catalytic entity of CPT1 and that foetal liver may contain a mixture of adult liver- and muscle-type enzymes. In rats made hypothyroid by administration of propylthiouracil and an iodine-deficient diet, hepatic CPT1 activity was decreased by 83%. However, CPT1 activity in extrahepatic tissues showed no adaptive decrease in hypothyroidism.
从成年大鼠肝脏、胎儿肝脏、肾皮质、心脏、骨骼肌和肩胛间棕色脂肪组织中分离出线粒体。DL-2-溴棕榈酰辅酶A抑制心脏、骨骼肌和棕色脂肪组织中肉碱棕榈酰转移酶（CPT1）的显性形式，半数抑制浓度（IC50值）为1.3 - 1.6微摩尔/升。相比之下，抑制肾脏或成年肝脏酶的IC50值为0.08 - 0.1微摩尔/升。近期胎儿肝脏中的CPT1与成年肝脏中的不同，2-溴棕榈酰辅酶A抑制其活性的IC50为0.57微摩尔/升。这表明CPT1的催化实体可能存在组织特异性形式，并且胎儿肝脏可能含有成年肝脏型和肌肉型酶的混合物。通过给予丙硫氧嘧啶和缺碘饮食使大鼠甲状腺功能减退，肝脏CPT1活性降低了83%。然而，甲状腺功能减退时肝外组织中的CPT1活性未出现适应性降低。
