Table 1.

Biometric characteristics in glycine N-methyltransferase-null mice

Body composition data are from glycine N-methyltransferase KO mice and WT littermates with free access to food and water. Data are mean ± S.E. for n = 21–25 mice/genotype. In a separate cohort of mice (“liver characteristics”), body weight, liver weight, and liver/body ratio were determined in WT and KO littermates following an 8-h fast. Data are for mean ± S.E. for n = 8–10 mice/genotype. Arterial plasma non-esterified fatty acids were obtained from catheterized WT and KO littermates undergoing stable isotope infusions 7 h and 40 min following food and water. Data are mean ± S.E. for n = 7–11 mice/genotype. Arterial plasma insulin and glucagon were obtained from catheterized KO and WT littermates undergoing stable isotope infusions 8 h following food and water withdrawal. For fasting studies, food and water were withdrawn during the first hour of the light cycle. Data are mean ± S.E. for n = 7–11 mice/genotype. Biometric characteristics were collected for male mice only. *, p < 0.05 versus WT.

Parameters	WT	KO
Body composition
Body weight (g)	25.4 ± 0.4	23.5 ± 0.4*
Lean mass (g)	18.2 ± 0.2	16.8 ± 0.3*
Fat mass (g)	1.9 ± 0.1	1.9 ± 0.1
Liver characteristics
Body weight (g)	23.9 ± 0.3	23.4 ± 1.1
Liver weight (g)	1.0 ± 0.0	1.6 ± 0.1*
Liver/body weight (%)	4.3 ± 0.1	6.9 ± 0.4*
Plasma hormones and metabolites
Plasma insulin (pmol/liter)	106 ± 24	90 ± 17
Plasma glucagon (pmol/liter)	17 ± 5	13 ± 4
Plasma non-esterified fatty acids (mmol/liter)	0.90 ± 0.04	0.94 ± 0.09