Table 1.

Quantitative evaluation of presynaptic expression of AMPAR subunits in dorsal horn

Antibody	Animal	Fixative	Laminas	Presynaptic staining	Synapses	Percentage
GluR2	R2411	4% PF	I –III	5	102	4.9
				4	92	4.3
	R2412	4% PF	I –III	5	93	5.4
				6	123	4.9
Total				20	410	4.9
GluR2/3	R2409	0.5% PF	III –IV	28	105	26.7
				22	81	27.2
	R2410	0.5% PF	III –IV	24	103	23.3
				19	98	19.4
Total				93	387	24.2
GluR4	R2399	4% PF+0.1% GA+0.1% PA	I –III	43	58	74.1
				43	55	78.2
	R2411	4% PF	I –III	39	53	73.6
				41	56	73.2
Total				166	222	74.8
GluR2/4	R2411	4% PF	I –III	73	96	76.0
				73	106	68.9
	R2412	4% PF	I –III	74	99	74.7
				72	98	73.5
Total				292	399	73.3

Counts are from EM grids immunostained with each of the AMPAR antibodies. For each subunit, counts are from two grids from each of two animals. All synapses in respective laminas that displayed immunolabeling in the presynaptic or postsynaptic profile or both were counted and are listed under Synapses. The number of such profiles in each grid in which immunolabeling was presynaptic is listed under Presynaptic staining. Percentages of presynaptic staining are listed in the last column. Pooled data for each subunit are shown in bold italics. PF, Paraformaldehyde; GA, glutaraldehyde; PA, picric acid.