title: Role of plasma protein and low-molecular weight substances in the change of hydroxyl radical scavenging activity in hemodialysis patients.
abstract: While it is well known that hemodialysis (HD) patients with end stage renal failure are exposed to high oxidative stress, there is not a general opinion regarding whether antioxidant activity is high or low in these patients. We evaluated the variation of plasma hydroxyl radical scavenging activity (p-HRSA) by a single-session of HD in 69 patients by using a new system, reactive flow-injection electron spin resonance. And then comparing p-HRSA with their biochemical parameters, we tried to elucidate what components affected p-HRSA in the HD patients. The average of p-HRSA significantly increased after HD and the variation of p-HRSA by HD was correlated with that of plasma total protein (TP). In 5 patients however, their p-HRSA decreased after HD, in spite of increasing TP. In pre-HD, the p-HRSA values and hydroxyl radical scavenging activity of low-molecular weight fraction of plasma were significantly higher in these 5 patients than in patients whose p-HRSA increased after HD. These 5 patients were in an inflammatory state. These findings suggest that p-HRSA is mainly affected by TP, but caution should be exercised in patients who have high p-HRSA before HD and whose p-HRSA does not increase after HD.
authors.affiliation: Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-0006, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Hirakawa
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Aoyagi
authors.forename: Motoo
authors.initials: M
authors.lastname: Nakajima
authors.forename: Syuichi
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Syoji
authors.initials: S
authors.lastname: Ohba
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Yamagata