Table 2.

Identity of postsynaptic profiles (dendritic spine or dendritic shaft) exhibiting synapses

	Adult		PD 7
	α7(+)	Total	α7(+)	Total
Spine	73.4  ± 5.7	71.5  ± 6.9	66.2  ± 5.7	67.2  ± 7.3
Shaft	9.4  ± 4.8	10.1  ± 3.1	10.3  ± 7.4	11.2  ± 7.9
Unidentified	17.2  ± 2.9	18.5  ± 4.6	23.5  ± 4.5	21.6  ± 4.0
		(n = 420)		(n = 270)

Note the prevalence of axon–spine junctions among both α7nAChR-positive and total asymmetric synapses in both age groups. Data (expressed as percentage of the total for each column) were gathered from a subset of all synapses examined in this study, including only synaptic profiles orthogonal to the section plane (those where the synaptic cleft was visible along the entire profile in electron micrographs). This subset of synapses was also used in Figures2 and 7-9. Mean and standard error are derived from three animals in each age group (124, 136, and 160 synapses from the three adult animals and 116, 71, and 82 synapses from the three PD 7 animals, respectively). Variations across cortical layers within each age group were not statistically significant, and data for all cortical layers are combined in the table.