Table 1.
Properties of mechanosensitive afferent fibers from incised skin of capsaicin- and vehicle-pretreated rats
| C-fibers Capsaicin |
Vehicle | Aδ-fibers Capsaicin |
Vehicle | |
|---|---|---|---|---|
| Total number of mechanonociceptors | 42 | 45 | 30 | 23 |
| Conduction velocity, m/s | 0.95 ± 0.08 (0.22-2.40) |
0.92 ± 0.08 (0.27-2.37) |
6.71 ± 0.90 (2.51-21.50) |
7.44 ± 1.29 (2.54-23.84) |
| Fibers with spontaneous activity | 16/42 (38.1%) |
22/45 (48.9%) |
4/30 (13.3%) |
6/23 (26.1%) |
| Median threshold (mN) | 40 | 40 | 40 | 40 |
| Heat-responsive fibers | 4/25 (16.0%)** | 26/29 (89.7%) | 2/21 (9.5%) | 2/14 (14.3%) |
| Acid-responsive fibers | 3/17 (17.6%)* | 9/16 (56.3%) | 0/9 (0.0%) | 1/9 (11.1%) |
Values for conduction velocity are means ± SE with ranges in parentheses; other values are number of fibers with percents in parentheses.
*
P < 0.05;
**
P < 0.001 vs. vehicle by χ2 test