Table 5

Comparison of pore dimensions of glutamate receptors determined by permeability to organic cations to measurements from other cation selective channels

Channel or Receptor	Pore Dimensions	Pore Area	References
	nm	nm²
Neuronal AMPA^5-a	0.6 diameter	0.28	Vyklicky et al., 1988
Neuronal NMDA^5-b	0.45 × 0.57	0.26	Zarei and Dani, 1995
GluR1^5-c	0.78 diameter	0.48	Burnashev et al., 1996
GluR1/GluR2	0.70 diameter	0.38	Burnashev et al., 1996
GluR6(Q)^5-c	0.75 diameter	0.44	Burnashev et al., 1996
GluR6(R)^5-c	0.76 diameter	0.45	Burnashev et al., 1996
GluR6(Q)/GluR6(R)	0.74 diameter	0.43	Burnashev et al., 1996
NR1-1a/NR2A	0.55 diameter	0.24	Villarroel et al., 1995; Wollmuth et al., 1996
5HT₃, serotonin^5-d	0.76 diameter	0.45	Yang, 1990; Yakel et al., 1990
Muscle nicotinic	0.65 × 0.65	0.42	Dwyer et al., 1980
Na⁺ Channel in frog nerve	0.31 × 0.51	0.16	Hille, 1992
K⁺ Channel in frog nerve	0.17 diameter^5-e	0.09	Hille, 1973; see Doyle et al., 1998
Ca²⁺ Channel in frog muscle	0.6 diameter^5-e	0.28	McCleskey and Almers, 1985

↵5-a Cultured chick cortical and diencephalic neurons.
↵5-b Cultured rat hippocampal neurons.
↵5-c Homomeric receptors.
↵5-d N18 neuroblastoma cells.
↵5-e Diameter calculated from area.