TABLE 3.

Metabolite levels during brain stimulation conditions in vivo and in vitro Data for glutamate (Glu), aspartate (Asp), and Lactate (Lact) content both at control (rest) and during brain work (stimulated) conditions from indicated Tables of the selected references are shown. ND, not determined in the original study; NMDA, N-methyl-d-aspartic acid.

System	Stimulation		Rest	Stimulated	Ref.
Rat dorsal cerebral cortex	5-min sensory stimulation	Glu	12.5 ± 0.6	13.3 ± 0.3	μmol/g wet weight (Ref. 18, see Tables 3 and 4)
		Asp	4.0 ± 0.3	3.3 ± 0.3
		Lact	0.6 ± 0.1	1.7 ± 0.4
Rat, microdialysis	Acoustic stimulation	Glu	ND	ND	mm (Ref 17, see Table V)
		Asp	ND	ND
		Lact	0.09 ± 0.02	0.2 ± 0.05
Rat dorsal cerebral cortex	Sensory stimulation	Glu	ND	ND	μmol/g wet weight (Ref. 16, see Table 2)
		Asp	ND	ND
		Lact	1 ± 0.5	1.9 ± 0.4
Mouse cerebral cortical slices	Repetitive K+ depolarization	Glu	48.6 ± 6.6	37.2 ± 7.6	nmol/mg protein (Ref. 85, see Table 1)
		Asp	20.7 ± 3.5	11.4 ± 3.7
		Lact	ND	ND
Cerebellar neuron culture	Repetitive NMDA and K+ depolarization	Glu	51 ± 17.2	42.9 ± 0.9	nmol/mg protein; lactate % labeling (Ref. 86, see Table 1)
		Asp	14.3 ± 21	10.1 ± 1.3
		Lact	5.6 ± 1.8	11.5 ± 0.9
In vivo human brain NMR spectroscopy	Visual cortex stimulation	Glu		+0.23 ± 0.01%	% change versus rest (Ref. 19, see Table 1)
		Asp		–14 ± 0.02%
		Lact		+24 ± 0.01%
Rat cortex	Bicuculline-induced seizure	Glu	11.8 ± 1.8	11.5 ± 1.1	μmol/g (Ref. 87, see Table 4)
		Asp	3.6 ± 0.8	2.8 ± 0.3
		Lact	3.2 ± 07	13 ± 4.9