Measurement of erythrocyte arginase activity and the effect of lead on the activity in vitro.
Measurement of arginase activity made by varying the arginine concentration and the reaction time clarified that the amount of urea formed by arginase peaked at the substrate concentration of 150 mmol/l, and increased linearly by 20 minutes. By using discs punched out from a dried blood filter paper prepared from identical human blood sample, the amount of formed urea showed linear increase up to 160 U/g.Hb. The coefficients of variation in ten measurements were 6.1% for the mean activity of 46.2 U/g.Hb and 2.1% for 152.1 U/g.Hb. No decreases in arginase activity were observed when two different dried blood filter papers were left for one week at room temperature. Intact erythrocytes were treated with various concentrations of lead from 0 to 5 mumols/l and their arginase activities were measured. The activity did not elevate linearly with the rise of lead concentration, but an almost diphasic elevation was observed. The arginase activity of erythrocytes treated with 5 mumols/l of lead was higher than that for untreated ones by 32%.
Fukumoto
K
K
Horiguchi
S
S
Nishikawa
Y
Y
D001119:Arginase / Q000097:blood*; D002478:Cells, Cultured; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D007854:Lead / Q000494:pharmacology*
D007854:Lead; D001119:Arginase