TABLE 2.

Metabolites labeled via the pyruvate recycling pathway in extracts of brain from 21–22 day old rats after injection of [2-¹³C]ALCAR

nmol 13C incorporated/mg protein#
	15 min	60 min	120 min
[2-13C]Lactate	0.194 ± 0.019	0.360± 0. 119	0.369± 0.098
[3-13C]Lactate	0.218 ± 0.053**	0.403 ± 0.101*	0.997 ± 0.179
[3-13C]Alanine	0.103 ± 0.024	0.183± 0.060	0.258± 0.052
[5-13C]Glutamate	0.545 ± 0.063*	0.581 ± 0.078*	0.970 ± 0.182
[5-13C]Glutamine	0.507± 0.037	0.569 ± 0.125	0.983 ± 0.242
[1-13C]Glutamate	0.579 ± 0.096**	0.781 ± 0.074*	1.417± 0.260
[1-13C]Glutamine	0.190 ± 0.036*	0.319 ± 0.086	0.490 ± 0.105

^#Data were obtained from peak integration of the ¹³C-NMR spectra as described in Methods. Percent enrichment was calculated from ¹³C labeling and total concentration as described in methods. Values are mean ± S.E. of data from n = 5 brains at 15 min, n=6 at 60 min, and n = 8 at 120 min. Data were analyzed using one-way ANOVA. Asterisks indicate values that are significantly different from 120 min time point,

^*p<0.05,

^**p<0.01.