Emv. Decavanagh et al., ENALAPRIL AND CAPTOPRIL ENHANCE ANTIOXIDANT DEFENSES IN MOUSE-TISSUES, American journal of physiology. Regulatory, integrative and comparative physiology, 41(2), 1997, pp. 514-518
This study was conducted to investigate a possible systemic effect of
angiotensin-converting enzyme inhibitors (ACEi) on tissue antioxidant
defenses. CF1 mice (4-mo-old females) were administered either water (
control) or water containing enalapril (20 mg/l) or captopril (50 mg/l
) during 11 wk. Neither enalapril nor captopril treatment had an effec
t on body mass or brain, kidney, or heart weight relative to controls.
CuZn-superoxide dismutase (SOD) activity was increased by enalapril t
reatment in kidney medulla (27%), heart (24%), and erythrocytes (19%)
and by captopril treatment in kidney medulla (43%) and heart (54%) rel
ative to controls. Mn-SOD and catalase activities were unaffected by e
ither treatment. Enalapril, but not captopril treatment, increased Se-
glutathione peroxidase activity in renal medulla (19%). Nonenzymatic a
ntioxidant defenses, evaluated by tert-butyl hydroperoxide-initiated c
hemiluminescence (HICL), were enhanced in kidney cortex (48%) by enala
pril and in brain by enalapril (44%) or captopril (36%) treatment rela
tive to controls. As evaluated in vitro by HICL and thiobarbituric aci
d-reactive substances formation, captopril had a free radical scavenge
r activity, whereas neither enalapril nor lisinopril was effective. Th
ese results suggest that ACEi may protect tissues from oxidative damag
e by increasing enzymatic and nonenzymatic antioxidant defenses.