新しい酵素法によるポリアミン測定について 第1報: 本法における尿中ポリアミン分別定量の基礎的検討

Abstract

ポリアミン測定は本法では尿中ポリアミン(PA)アセチル抱合体をacylpolyamine amidohydrolaseで遊離型ポリアミンとして, 基質特異性の異なる2種類のアミン酸化酵素で分別定量をする.その基礎的検討の結果, 1)酵素加水分解による尿中PAの回収率はDiamine 95±4%, Spermidine 95±1%, Spermine 99±2%と良好であり, 更にそれぞれ150 μmole/l, 75 μmole/l, 及び50 μmole/lまでいずれも良好な直線性が得られた.2)尿中PAの日内変動はクレアチニン補正でも認められたが, 日差変動はクレアチニン補正で一定した値が得られた.3) 24時間蓄尿と早朝尿の尿中PAの比較検討ではDiamine, Spermidine, Spermineとも比較的良好な相関関係が得られた.4)尿中PAは尿中白血球, 赤血球による影響をうけなかった

A new enzymatic method for determining urinary polyamine concentration by fractionation of the urinary acetyl conjugate into free polyamines with acylpolyamine amido-hydrolase and quantification using two kinds of amine-oxidase of different substrate specificity was examined. High recovery rates of urinary polyamine by enzymatic hydrolyzation were obtained, namely, 95 +/- 4% for diamine, 95 +/- 1% for spermidine and 99 +/- 2% for spermine. Furthermore, excellent linearity was demonstrated with up to 150 mumole/l diamine, up to 75 mumole/l spermidine and up to 50 mumole/l spermine. Although urinary polyamine concentration varied diurnally even after correction of urinary creatinine, day-to-day variation disappeared. In 24-hour pooled urine and voluntary urine, diamine, spermidine and spermine correlated relatively well. Urinary leukocytes and erythrocytes exerted no influence on urinary polyamine.