Table 1.
NCS before and at 7, 21, and 42 days of HDT in rhesus monkeys (n = 6)
| Time points | Parameters | Median | Ulnar | Tibial | Fibular |
|---|---|---|---|---|---|
| Before HDT | MCV (m/s) | 59.55 ± 6.20 | 62.67 ± 9.02 | 57.45 ± 4.50 | 60.32 ± 4.94 |
| Proximal CMAP (mV) | 8.40 ± 2.66 | 4.33 ± 1.87 | 11.87 ± 3.19 | 7.72 ± 4.60 | |
| Distal CMAP (mV) | 10.25 ± 3.40 | 5.58 ± 2.05 | 11.17 ± 2.68 | 7.68 ± 4.15 | |
| 7 days | MCV (m/s) | 53.15 ± 4.76 | 56.53 ± 14.41 | 52.66 ± 5.61 | 55.50 ± 8.16 |
| Proximal CMAP (mV) | 7.70 ± 1.50 | 5.25 ± 3.36 | 12.98 ± 4.99 | 6.48 ± 4.91 | |
| Distal CMAP (mV) | 7.28 ± 1.27† | 6.58 ± 3.60 | 12.86 ± 5.03 | 7.00 ± 3.26 | |
| 21 days | MCV (m/s) | 58.45 ± 6.86 | 63.03 ± 8.00 | 51.98 ± 6.74 | 56.42 ± 5.15 |
| Proximal CMAP (mV) | 4.38 ± 2.83* | 2.95 ± 1.40 | 8.48 ± 3.52 | 5.28 ± 2.84 | |
| Distal CMAP (mV) | 5.05 ± 2.01† | 4.13 ± 1.53 | 10.84 ± 3.00 | 5.74 ± 2.34 | |
| 42 days | MCV (m/s) | 57.45 ± 3.16 | 61.8 ± 1.82 | 52.36 ± 8.38 | 57.00 ± 6.53 |
| Proximal CMAP (mV) | 3.30 ± 2.70*,§ | 2.50 ± 2.43 | 6.14 ± 1.94‡,¶ | 5.38 ± 4.05 | |
| Distal CMAP (mV) | 3.95 ± 2.79†,|| | 4.03 ± 4.08 | 8.04 ± 2.86 | 5.06 ± 4.32 |
Data represent means ± SDs. *For the median nerve, statistically different versus the proximal CMAP before HDT; †For the median nerve, statistically different versus distal CMAP before HDT; ‡For the tibial nerve, statistically different versus the proximal CMAP before HDT; §For the median nerve, statistically different versus the proximal CMAP 7 days of HDT; ||For the median nerves, statistically different versus distal CMAP 7 days of HDT; ¶For the tibial nerve, statistically different versus the proximal CMAP 7 days of HDT. NCS: Nerve conduction study; HDT: Head-down tilt; MCV: Motor conduction velocity; CMAP: Compound muscle action potential; SDs: Standard deviations.