TABLE 1.

Nitrite concentrations in culture supernatants of uninfected J774 or L2 cells following addition of IFN-γ, LPS, or aminoguanidine

Additive (concn)	Nitrite concn (μM) in:
	J774 cells at 16 ha	L2 cells
		16 h	48 h
None	<1.6b	<1.6	<1.6
IFN-γ (100 U/ml)	<1.6	<1.6	<1.6
IFN-γ (100 U/ml) + LPS (1 mg/ml)	31.3 ± 12.5c	<1.6	<1.6
IFN-γ (100 U/ml) + LPS (1 mg/ml) + aminoguanidine (2 mM)	<1.6	<1.6	<1.6

^aTime period of treatment with additive. 

^b<1.6 μM, below the limits of detection. 

^cMean ± standard deviation.