ビタミンB_6大量投与によるTyrosine Transaminaseの誘導合成の機構について

概要

論文の詳細を見る
Intraperitoneal as well as oral administration of pyridoxine 50mg/100g to rats resulted in a 2 to 3-fold rise of hepatic tyrosine transaminase (L-tyrosine 2-oxaloglutarate aminotransferase EC 2. 6. 1. 5.), the maximum activity being attained 4 hours after administration. This rise was also observed by intraperitoneal injection of other vitamins such as B_1,B_2 or nicotinic acid. Bilateral adrenalectomy curtailed the rise by pyridoxine or pyridoxal administration but still a 150 per cent increase of the activity was observed on 2 to 4 days after the operation, while injection of pyridoxamine and other vitamins had no effect on the adrenalectomized rats. The induction of tyrosine transaminase, which is according to kenney^<6)> due to an increased rate of its de novo synthesis, was no more seen on the 7th day after adrenalectomy. The inductibility was restored by the pretreatment of rats wite hydrocortisone 5mg/100g 15 hours before the injection of pyridoxine. This phenomena together with the fact that the day course of change of induction by pyridoxine after adrenalectomy seems to reflect that of serum corticosterone of adrenalectomized rats as reported by Fazekas, supports the conclusion that the induction of tyrosine transaminase by pyridoxine is a secondary change mediated by glucocorticoid. (Received June 13,1970)
日本ビタミン学会の論文
1970-09-25