Premium
Reduction in superoxide dismutases and catalase contributes to oxidative stress and neurogenic hypertension in spontaneously hypertensive rats
Author(s) -
Chan Julie Y.H.,
Wang LingLin,
Chan Samuel H.H.
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.6.a891-c
Subject(s) - sod2 , superoxide dismutase , rostral ventrolateral medulla , oxidative stress , sod1 , endocrinology , medicine , catalase , chemistry , glutathione peroxidase , superoxide , reactive oxygen species , downregulation and upregulation , dismutase , enzyme , biochemistry , medulla oblongata , central nervous system , gene
The present study assessed the hypothesis that augmented superoxide anion (O 2 ·− ) and hydrogen peroxide (H 2 O 2 ) levels because of the reduction in superoxide dismutase (SOD), catalase (CAT) or glutathione peroxidase (GPx) in the rostral ventrolateral medulla (RVLM), where sympathetic premotor neurons are located, contribute to the pathogenesis of hypertension. We found that cupper/zinc SOD (SOD1), manganese SOD (SOD2) or CAT, but not GPx, mRNA or protein expression and enzyme activity in the RVLM of spontaneously hypertensive rats (SHR) was significantly lower than that in normotensive Wistar‐Kyoto (WKY) rats, along with a significantly higher level of O 2 ·− or H 2 O 2 . Microinjection of adenovirus encoding SOD1, SOD2 or CAT into the bilateral RVLM promoted a long‐lasting reduction in arterial pressure in SHR, but not WKY rats; accompanied by an enhanced SOD1, SOD2 or CAT protein expression or enzyme activity and reduced O 2 ·− or H 2 O 2 level in the RVLM. These results suggest that downregulation of gene expression and enzyme activity of the antioxidant SOD1, SOD2 or CAT may underlie the augmented levels of O 2 ·− and H 2 O 2 in the RVLM, leading to oxidative stress and hypertension in SHR.