McMillin Wood J
J Biol Chem. 1975 Apr 25;250(8):3062-6.
Carnitine palmityltransferase was measured in neonatal and adult rat heart and liver mitochondria. When compared to the adult, no developmental differences in liver mitochondrial carnitine palmityltransferase were seen 24 hours postpartum. In neonatal heart, enzyme activity was initially low, reaching adult levels by 20 days. Polarographic measurements of oxygen consumption revealed normal levels of palmityl coenzyme A oxidation in the presence of carnitine and of palmitylcarnitine oxidation in both neonatal heart and liver. Phospholipase C treatment produced higher specific activities of carnitine palmityltransferase in neonatal and activities of carnitine palmityltransferase in neonatal and adult liver, probably due to decreases in total mitochondrial protein. Phospholipase C treatment had no effect on adult rat heart carnitine palmityltransferase but increased neonatal heart enzyme activity to adult levels. Low levels of measured enzyme activity were proposed to be due to "masking" of enzyme expression in intact mitochondrial preparations.
对新生大鼠和成年大鼠的心脏及肝脏线粒体中的肉碱棕榈酰转移酶进行了测定。与成年大鼠相比，产后24小时肝脏线粒体肉碱棕榈酰转移酶未见发育差异。在新生大鼠心脏中，酶活性最初较低，到20日龄时达到成年水平。极谱法测定的氧消耗量显示，在肉碱存在的情况下，新生大鼠心脏和肝脏中棕榈酰辅酶A的氧化水平正常，棕榈酰肉碱的氧化水平也正常。磷脂酶C处理使新生大鼠和成年大鼠肝脏中肉碱棕榈酰转移酶的比活性升高，这可能是由于线粒体总蛋白减少所致。磷脂酶C处理对成年大鼠心脏肉碱棕榈酰转移酶没有影响，但使新生大鼠心脏的酶活性提高到成年水平。酶活性测定值较低被认为是由于完整线粒体制剂中酶表达被“掩盖”所致。
