Kidney mitochondrial nitric oxide synthase

BOVERIS A; VALDEZ LB; ALVAREZ S; ZAOBORNYJ T; BOVERIS AD; NAVARRO A

Antiox Redox Signal

Año: 2003 vol. 5 p. 265 - 271

Nitric oxide synthase (mtNOS) activity was recognized in rat renal cortex mitochondria with NO production rates of 0.14-0.78 nmol/(min.mg protein). Rat pretreatment with enalapril (30 mg/(kg.day) i.p., up to 15 d) increased NO production in kidney, liver and heart mitochondria. In kidney, mtNOS activity and mtNOS protein, measured by Western blot densitometry, were 5 and 2.3 times increased, respectively. EPR analysis with the probe MGD-Fe detected NO production in mitochondria isolated from enalapril-treated rats, but not in control untreated animals. Polyclonal antibodies anti-iNOS and anti-nNOS detected kidney mtNOS in Western blots and inhibited mtNOS biochemical activity. The enzymatic activity of kidney mtNOS generates intramitochondrial NO concentrations that regulate mitochondrial functions: state 3 respiration was decreased by 12-28 %; and state 4 H2O2 production was increased 12-35 %.