Table 1.

Effect of intraarterial infusion of nitrite on venous plasma nitrite concentration and FBF in one representative individual (for details see Results)

Nitrite infusion, nmol/min	Theoretical venous NO, ΔμM	Measured NO, ΔμM	Estimated recovery, %	ΔFBF, ml/min/100 ml of tissue
10	0.05	0.046	92	0
30	0.15	0.145	97	−0.1
100	0.50	0.469	94	0

Theoretical nitrite concentrations in venous blood were estimated based on a resting flow through the forearm circulation of ≈200 ml/min. Venous plasma nitrite concentrations were measured in samples drawn 1 min after start of nitrite infusion and were corrected for arterial nitrite inflow (basal arterial NO concentration: 262 nM).