Electrophysiological properties of DRG neurons with functionally identified peripheral receptive fields
| Size Category | Large | Medium | Small | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Submodality | MS | LTM | HTM | MS | LTM | HTM | LTM | HTM | MH |
| Cell size, um | 58.2 ± 2.3 | 57.1 ± 1.7 | 50.0 | 38.9 ± 1.3 | 41.1 ± 0.5 | 36.6 ± 1.3 | 30.0 | 26.3 ± 0.8 | 24.4 ± 1.5 |
| n | 27 | 27 | 1 | 7 | 11 | 9 | 1 | 27 | 17 |
| CVdr, m/s | 16.6 ± 1.4 | 14.7 ± 1.4 | 10.6 | 11.0 ± 1.5 | 6.56 ± 1.02 | 6.21 ± 1.16 | 0.61 | 0.41 ± 0.03 | 0.38 ± 0.03 |
| n | 17 | 25 | 1 | 2 | 11 | 7 | 1 | 20 | 11 |
| Curr. Thre., nA | 1.19 ± 0.26 | 1.41 ± 0.16 | 3.40 | 0.58 ± 0.14 | 1.21 ± 0.12 | 1.76 ± 0.67 | 1.20 | 0.87 ± 0.11 | 0.56 ± 0.11 |
| n | 14 | 16 | 1 | 4 | 10 | 7 | 1 | 18 | 11 |
| APD50, ms | 0.48 ± 0.08 | 0.53 ± 0.07 | 0.45 | 0.55 ± 0.10 | 0.77 ± 0.10 | 0.92 ± 0.09 | 1.74 | 2.90 ± 0.43 | 3.31 ± 0.49 |
| n | 11 | 18 | 1 | 6 | 11 | 8 | 1 | 15 | 9 |
| AP amp., mV | 54.4 ± 3.1 | 57.1 ± 2.7 | 76.5 | 50.5 ± 1.5 | 64.5 ± 3.0 | 69.1 ± 3.3 | 69.3 | 74.4 ± 3.7 | 67.7 ± 3.5 |
| n | 11 | 17 | 1 | 5 | 10 | 8 | 1 | 15 | 9 |
| AHP50, ms | 2.35 ± 0.28 | 3.69 ± 0.40 | 15.1 | 2.01 ± 0.23 | 3.21 ± 0.25 | 8.11 ± 1.80 | 3.17 | 9.24 ± 1.14 | 8.96 ± 2.04 |
| n | 11 | 18 | 1 | 6 | 10 | 8 | 1 | 14 | 9 |
-
Values are given in means ± SE, and n = sample size. Neurons were classified by peripheral receptor type, i.e., muscle spindle (MS), cutaneous low-threshold mechanoreceptor (LTM), cutaneous high-threshold mechanosensitive nociceptor (HTM), and cutaneous mechano-heat nociceptor (MH) (3 of which also responded to cold). One mechanoheat sensitive nociceptive medium sized soma and and one heat-only nociceptive small sized soma are not included. CVdr: dorsal root conduction velocity, AP amp.: amplitude of action potential. Other parameters are same as Table 1.