Chesnokov V N, Gadzhiev V G, Leontyeva G I, Zelenin S M, Mertvetsov N P
Novosibirsk Institute of Bioorganic Chemistry, Siberian Division, USSR Academy of Sciences.
Biomed Biochim Acta. 1990;49(12):1177-86.
Treatment of Wistar rats with a single dose of hydrocortisone acetate resulted in a transient induction of tyrosine aminotransferase (TAT) in the liver. TAT activity and the level of TAT mRNA increased 4-6 h after addition of hydrocortisone acetate (induction phase) and declined thereafter (deinduction phase). TAT activity and TAT mRNA failed to respond to readdition of fresh hydrocortisone acetate during the deinduction period, but cycloheximide treatment at this period increased the level of TAT mRNA. Hydrocortisone acetate alone and cycloheximide alone or after hydrocortisone acetate treatment stimulated the rate of TAT gene transcription. TAT displayed a low activity in the rat heart, brain and kidney, and was not induced by hydrocortisone acetate in these tissues. In addition to liver, TAT mRNA was found in heart, brain and kidney, but in the latter three tissues its amount was about one tenth only as in the liver, which was consistent with different levels of TAT activity. Upon hydrocortisone acetate treatment the TAT mRNA levels in brain and heart remained unchanged.
用单剂量醋酸氢化可的松处理Wistar大鼠会导致肝脏中酪氨酸转氨酶（TAT）的短暂诱导。添加醋酸氢化可的松后4 - 6小时，TAT活性和TAT mRNA水平升高（诱导期），此后下降（去诱导期）。在去诱导期，TAT活性和TAT mRNA对重新添加新鲜醋酸氢化可的松无反应，但在此期间用环己酰亚胺处理可增加TAT mRNA水平。单独的醋酸氢化可的松以及单独的环己酰亚胺或在醋酸氢化可的松处理后均可刺激TAT基因转录速率。TAT在大鼠心脏、大脑和肾脏中活性较低，且在这些组织中不会被醋酸氢化可的松诱导。除肝脏外，在心脏、大脑和肾脏中也发现了TAT mRNA，但在后三种组织中其含量仅为肝脏中的十分之一左右，这与不同水平的TAT活性一致。经醋酸氢化可的松处理后，大脑和心脏中的TAT mRNA水平保持不变。
