Enhanced S-Nitroso-Albumin Formation From Inhaled NO During Ischemia/Reperfusion

ESM Ng, D Jourd'heuil, JM McCord… - Circulation …, 2004 - Am Heart Assoc
ESM Ng, D Jourd'heuil, JM McCord, D Hernandez, M Yasui, D Knight, P Kubes
Circulation research, 2004Am Heart Assoc
In the present study, we investigated whether inhaled nitric oxide (NO) was transported by
plasma proteins, such as S-nitroso-albumin (SNO-Alb), in the feline circulation and whether
this molecule delivers NO to the periphery under conditions of stress, specifically
ischemia/reperfusion (I/R). A flow probe was interposed between the femoral and superior
mesenteric artery for blood flow measurements, and a branch of the superior mesenteric
vein was cannulated for arterial-venous sampling. In animals breathing room air, SNO-Alb …
In the present study, we investigated whether inhaled nitric oxide (NO) was transported by plasma proteins, such as S-nitroso-albumin (SNO-Alb), in the feline circulation and whether this molecule delivers NO to the periphery under conditions of stress, specifically ischemia/reperfusion (I/R). A flow probe was interposed between the femoral and superior mesenteric artery for blood flow measurements, and a branch of the superior mesenteric vein was cannulated for arterial-venous sampling. In animals breathing room air, SNO-Alb was below detection level in arterial or venous blood. NO inhalation resulted in a significant arterial-venous gradient for SNO-Alb. Concomitant with this loss of SNO-Alb across the intestinal vasculature was an increase in nitrite (NO2). However, this release of NO was not sufficient to alter intestinal blood flow. I/R during NO inhalation caused a very large increase in arterial SNO-Alb that permitted a 5-fold increase in SNO-Alb consumption and significant generation of NO2 within the postischemic intestinal vasculature. The increased SNO-Alb consumption was sufficient to dramatically improve intestinal blood flow. The very large burst of arterial SNO-Alb during I/R was completely blocked by the administration of superoxide dismutase, suggesting that oxidative stress contributed to the increased SNO-Alb formation. Our data suggest that inhaled NO can increase nitrosothiol production and these molecules may be a functional NO delivery system during cardiovascular disease.
Am Heart Assoc