Table 5

Concentrations of transmitters in the vesicle, synaptic cleft, and extracellular space

	Concentration	Transmitter	Location	Reference
Vesicle	90 mM	DA	Brain (rat)	Floor et al., 1995
	10 mM	NE	Hypothalamic synaptosome	West and Fillenz, 1980
	90 mM	5-HT	Dorsal raphe	Bunin and Wightman, 1998, 1999
	60–210 mM	Glu	Hippocampus	Burger et al., 1989; cf.Clements, 1996
	60 mM	ACh	Neuromuscular junction	Van der Kloot and Molgo, 1994
Synaptic cleft	6 mM	5-HT	Dorsal raphe	Bunin and Wightman, 1998
	∼1 mM	ACh	Neuromuscular junction	Matthews-Bellinger and Salpeter, 1978; Kuffler and Yoshikami, 1975
	∼1–5 mM	GABA	Hippocampus	Clements, 1996
	∼1 mM	Glu	Hippocampus	Clements et al., 1992
Extracellular space	55 nM	5-HT	Dorsal raphe substantia nigra	Bunin and Wightman, 1998, 1999; Bunin et al., 1998
	10 μM	GABA	Hippocampus	Destexhe and Sejnowski, 1995
	0.2–0.8 μM	GABA	Hippocampus	Lerma et al., 1986
	5–55 nM	NA	Cortex	Allgaier et al., 1992
	100 nM	NA	Hippocampus	Kiss et al., 1995
	0.1–1 nM	ACh	Hippocampus	Moor et al., 1995
	3 μM	DA	Striatum	Taber and Fibiger, 1994; Benveniste and Hüttemeier, 1990
	0.1–1 μM	DA	Striatum	Kawagoe et al., 1992