Table 3.

Baseline and steady state plasma isotopic enrichments on study days 1 and 2 during period A and on study days 3 and 4 during period B

Study day	[U-13C]lysine		[2H4]lysine
	Baseline	Plateau	Baseline	Plateau
	(mol%)	(mol%)	(mol%)	(mol%)
1	0.0010 (0.0006)	0.0345 (0.0042)	0.0019 (0.0008)	0.0201 (0.0045)
2	0.0019 (0.0007)	0.0315 (0.0040)	0.0042 (0.0019)	0.0360 (0.0067)
3	0.0018 (0.0005)	0.0372 (0.0100)	0.0028 (0.0008)	0.0324 (0.0061)
4	0.0059 (0.0065)	0.0362 (0.0074)	0.0031 (0.0005)	0.0461 (0.0094)

Values are means (SD); n = 6 on study days 1 and 2 and n = 4 at study days 3 and 4.

On study days 1 and 3 [U-¹³C]lysine was administered by intravenous infusion and [²H₄]lysine by intragastric infusion, and on study days 2 and 4 [U-¹³C]lysine was given by intragastric infusion and [²H₄]lysine by intravenous infusion.