Table 1.

The numbers and densities of 5-HT and NA terminals in apposition with the cell bodies and dendrites of seven commissural interneurons

		Soma							Dendrites
		Total number of contacts		Number of contacts			Contact density (n/100μm²)			Number of contacts			Contact density (n/100μm²)
Inputs/Lamina VIII subpopulation	Inter neurons ID	5HT	NA	5HT	NA	Surface area²) (μm	5HT	NA	Total dendritic length (μm)	5HT	NA	Surface area²) (μm	5HT	NA
Group II, monosynaptic inputs
Group II	1	83	45	9	2	1480.64	0.61	0.14	4841.3	74	43	38299.6	0.19	0.11
	2	203	16	0	0	3698.49	0	0	12570.1	209	16	85365.6	0.24	0.02
Group II, disynaptic and RF inputs
Group II and RF	3	86	28	0	0	2005.91	0	0	8054.3	86	28	64073.1	0.13	0.04
	4	55	2	3	0	5396.92	0.02	0	5336.2	52	2	53977.3	0.1	0.004
RF inputs
RF	5	156	7	0	0	1687.16	0	0	9294.8	156	7	45355.6	0.34	0.02
	6	152	40	3	0	2600.82	0.12	0	10251.6	149	40	84972.7	0.18	0.05
	7	63	10	0	0	2103.09	0	0	5339.3	63	10	36006.5	0.17	0.03
Group II input
Intermediate zone Group II*
Mean (SD)	1–5	140 (28)	37.8 (13)	6.2 (2.8)	2 (2.1)	4769.6 (1926.8)	0.13 (0.07)	0.04 (0.03)	3727.26 (1046.76)				0.29 (0.05)	0.08 (0.03)

Contacts for cells 2, 3, 4 and 6 are illustrated in Figs 7 and 8. *Similar data for another population of interneurons with group II input, those located in the intermediate zone and projecting to ipsilateral motor nuclei (Maxwell et al., 2000).