TABLE 1.
Numbers of Descending Brain Neurons That Project to 20% BL in the Spinal Cord
| Cell group | 4-Week recovery1 | 8-Week recovery1 | Normal2 |
|---|---|---|---|
| N | 29 | 18 | 11 |
| Body length (mm) | 93.7 ± 9.5 | 84.9 ± 7.1 | 90.9 ± 6.1 |
| Di | 0.2 ± 0.53 | 6.9 ± 4.5 | 20.4 ± 9.2 |
| M cells (M1–M3) | 0.1 ± 0.4 | 2.6 ± 1.7 | 6.0 ± 0.0 |
| MRN | 1.1 ± 2.0 | 32.4 ± 9.5 | 55.3 ± 16.9 |
| I cells (I1–I4) | 0.5 ± 1.4 | 3.1 ± 1.9 | 8.0 ± 0.0 |
| aARRN | 3.1 ± 4.3 | 35.4 ± 9.8 | 61.0 ± 13.5 |
| IARRN | 2.2 ± 4.1 | 40.3 ± 10.7 | 69.0 ± 10.7 |
| mARRN | 2.2 ± 3.9 | 26.7 ± 5.1 | 38.0 ± 8.7 |
| B cells (B1–B5) | 0.1 ± 0.3 | 3.6 ± 1.9 | 9.6 ± 0.6 |
| Mau and AM cells | 0.1 ± 0.3 | 1.5 ± 1.1 | 4.0 ± 0.0 |
| aMRRN | 2.8 ± 4.5 | 33.0 ± 8.0 | 54.1 ± 11.9 |
| pMRRN | 7.6 ± 9.4 | 52.1 ± 11.7 | 72.1 ± 8.6 |
| PRRN | 25.7 ± 30.5 | 259.6 ± 49.5 | 539.5 ± 85.9 |
| ALV | 0.8 ± 1.5 | 10.9 ± 4.0 | 20.3 ± 2.7 |
| DLV | 0.5 ± 0.9 | 12.1 ± 8.1 | 57.7 ± 14.9 |
| PLV | 6.7 ± 9.2 | 58.4 ± 25.5 | 116.8 ± 28.0 |
| PON | 0.0 ± 0.0 | 0.8 ± 0.9 | 13.0 ± 3.0 |
1
Control animal groups (spinal cord transection at 10% BL, and following 4-week or 8-week recovery times, application of HRP to the spinal cord at 20% BL; see Fig. 1A).
2
For comparison purposes, the numbers of descending brain neurons in normal animals that are retrogradely labeled by application of HRP to the spinal cord at 20% BL; total numbers of labeled neurons = 1,141 ± 140 (data from Zhang et al., 2002).
3
Mean ± SD for numbers of labeled descending brain neurons on both sides of brain that projected to the HRP application site in the spinal cord at 20% BL.