The role of oxygen and reduced oxygen species in nitric oxide-mediated cytotoxicity: studies in the yeast Saccharomyces cerevisiae model system.
The cytotoxicity of nitric oxide (NO) is well established, yet the mechanism(s) of its cytotoxicity is (are) still undefined and a matter of significant interest and speculation. Many of the previously proposed mechanisms for NO-mediated cytotoxicity involve interactions between NO and molecular oxygen (O(2)) and/or O(2)-derived species such as O(-)(2) and H(2)O(2). The yeast Saccharomyces cerevisiae represents a useful model system for evaluating the role of O(2) and O(2)-derived species in NO-mediated cytotoxicity. This study examines the contribution of O(2) and O(2)-derived species to NO-mediated cytotoxicity in the yeast S. cerevisiae. NO-mediated cytotoxicity was determined to be O(2)-dependent. However, this O(2) dependence was only minimally due to the generation of O(2)-derived species such as O(-)(2) and/or H(2)O(2).
Chiang
K T
KT
Department of Pharmacology, UCLA School of Medicine, Los Angeles, California 90095-1735, USA.
Switzer
C H
CH
Akali
K O
KO
Fukuto
J M
JM
D006861:Hydrogen Peroxide / Q000633:toxicity; D009566:Nitrates / Q000633:toxicity; D009569:Nitric Oxide / Q000633:toxicity*; D010100:Oxygen / Q000633:toxicity*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000187:drug effects*
D009566:Nitrates; C039642:peroxynitric acid; D009569:Nitric Oxide; D006861:Hydrogen Peroxide; D010100:Oxygen