. Author manuscript; available in PMC: 2014 Jul 2.

Published in final edited form as: J Comp Neurol. 2012 Apr 15;520(6):1198–1211. doi: 10.1002/cne.22768

TABLE 2.

Morphometric Analysis of SPNs and PPNs¹

Age	Dorsoventral length of SPNs (d_SPN)	Distance between SPNs and SMNs (d_SPN-SMN)	Dorsoventral length of PPNs (d_PPN)	Distance between PPNs and SMNs (d_PPN-SMN)
E13.5
+/+	0.208 ± 0.005	0.081 ± 0.007	0.244 ± 0.039	nd
+/−	0.266 ± 0.004^**	0.029 ± 0.004^**	0.295 ± 0.017	nd
E14.5
+/+	0.138 ± 0.003	0.211 ± 0.004	0.119 ± 0.006	0.274 ± 0.022
+/−	0.246 ± 0.006^**	0.080 ± 0.008^**	0.203 ± 0.011^**	0.168 ± 0.030^*
E17.5
+/+	0.112 ± 0.003	0.270 ± 0.006	0.137 ± 0.006	0.464 ± 0.006
+/−	0.218 ± 0.007^**	0.132 ± 0.006^**	0.221 ± 0.008^**	0.322 ± 0.012^**
P0
+/+	0.104 ± 0.003	0.322 ± 0.008	0.152 ± 0.008	0.521 ± 0.019
+/−	0.275 ± 0.146^**	0.182 ± 0.011^**	0.304 ± 0.025^**	0.329 ± 0.026^**

Abbreviations: PPN, parasympathetic preganglionic neuron; SMN, somatic motor neuron; SPN, sympathetic preganglionic neuron; nd, not done (unable to measure due to indistinct boundaries between neuronal populations).

All distances were normalized with respect to the total gray matter length along the dorsoventral axis to account for developmental variation in spinal cord sizes.

P < 0.01.

^**

P < 0.0001.