Whitehead V M, Kamen B A, Beaulieu D
Department of Pediatrics, McGill University-Montreal Children's Hospital Research Institute, Quebec.
Cancer Drug Deliv. 1987;4(3):185-9. doi: 10.1089/cdd.1987.4.185.
Levels of dihydrofolate reductase (DHFR) were measured in livers from man and a variety of animals and birds to explore possible causes for the remarkably low levels of DHFR previously reported in fresh human tissues, including liver (Cancer Drug Delivery 2, 133 (1985)). While levels were lower in wild than domesticated animals and birds, suggesting a possible role for folic acid supplements fed to the latter, levels in both were far higher than in humans. Hepatic DHFR levels were similar in adult and young animals, birds and humans. In primates, monkey livers had DHFR levels similar to those of other animals, while levels in great apes were much lower and closer to levels in man. These findings suggest that low levels of DHFR are a feature peculiar to man, which is shared with the primates closest to man, but which distinguishes him from most animals and birds.
测量了人类以及各种动物和鸟类肝脏中二氢叶酸还原酶（DHFR）的水平，以探究先前报道的新鲜人体组织（包括肝脏）中DHFR水平极低的可能原因（《癌症药物递送》第2卷，第133页（1985年））。虽然野生动物体内的DHFR水平低于家养动物和鸟类，这表明喂养给后者的叶酸补充剂可能发挥了作用，但两者的水平都远高于人类。成年和幼年动物、鸟类以及人类的肝脏DHFR水平相似。在灵长类动物中，猴子肝脏的DHFR水平与其他动物相似，而类人猿的水平则低得多，更接近人类的水平。这些发现表明，低水平的DHFR是人类特有的特征，与最接近人类的灵长类动物相同，但这使人类与大多数动物和鸟类有所区别。
