Detection of nitric oxide reduction during ischaemia - reperfusion by EPR spectroscopy

ABSTRACT

Acute renal failure is a common consequence of sepsis due to concurrent renal ischaemia. The role of nitric oxide [NO] in endotoxaemia and in ischaemic injury in the kidney is not well defined. In this study we have used an animal model of sepsis induced by injection of bacterial lipopolysaccharide [LPS] in the rat and measured renal nitric oxide by X-band electron paramagnetic resonance [EPR] spectroscopy using the spin trap Fe [2+]-N-methyl-D- glucamine dithiocarbamate [Fe[MGD]2] given by intravenous injection 6 minutes before sacrifice, The characteristic EPR spectrum of [Fe[NO][MGD]2] was observed in kidneys of rats treated with LPS for 5h. Rat kidneys subjected to 20 min ischaemia and 5 min reperfusion had lower concentrations of [Fe[NO][MGD]2] [1.0 +/- 0.6 [M] compared to the controlateral nonischaemic-kidneys [1.5 +/- 0.9 [M, P<0.05]. This study shows reduced levels of NO after renal ischaemia in vivo