Table 1.

Twenty numbered anti-Cx36-immunogold-labeled and grid-mapped gap junctions in adult rat hippocampus, with their anatomical locations, size ranges (number of connexons, if countable), and their associations with labeled and unlabeled glutamate receptor PSDs (as tight patches of 10-nm E-face IMPs) vs. dispersed 10-nm E-face IMPs that are thought to represent extrasynaptic or “reserve” receptors.

GJ location	No. of GJs	GJ size range	GJs near E-face PSDs	GJs near clusters of 10-nm E-face IMPs	GJs on spines*	GJs on MF axon terminals	Dendrodendritic GJs	GJs in unidentified cell pairs
Dentate gyrus	4	45–220	H19	H19	H19	0	0	H4, H5, H6
Hilus	3	49–325	0	H8, H9	H8, H9	0	0	H20
CA3 lucidum	6	50–330	H3	H22	H3, H18, H22	H1, H17	H2	0
CA3 oriens	5	150–1150	H10	H10, H13	H13	0	H12	H11, H21
CA1 oriens	1	490	0	0	0	0	0	H14
CA1 radiatum	1	492	0	0	0	0	0	H7

Also indicated are gap junctions where specific distinguishing features were not identifiable in either neuron. Some numbered gap junctions appear in multiple columns.

GJ, gap junction; size range, number of connexons, from smallest to largest; PSD, postsynaptic density; IMP, intramembrane particle; SVs, synaptic vesicles; *with the other cell not identified.