Table 1.
Classification of VcPbT neurons responsive to various agents
| Mechanical Classification |
Thermal Classification |
Recording Point |
||||||
|---|---|---|---|---|---|---|---|---|
| Agent | Responsive | HT | WDR | LT | Heat | Cold | sDH | dDH |
| 5-HT | 28 of 45 (62%) | 12 (43%) | 12 (43%) | 4 (14%) | 16 (57%) | 11 (39%) | 24 (86%) | 4 (14%) |
| β-ALA | 1 of 37 (3%) | 0 | 1 (100%) | 0 | 1 (100%) | 0 | 1 (100%) | 0 |
| HA | 11 of 37 (30%) | 4 (36%) | 5 (45%) | 2 (18%) | 6 (55%) | 3 (27%) | 9 (82%) | 2 (18%) |
| CQ | 13 of 41 (32%)* | 3 (23%) | 9 (69%) | 1 (8%) | 10 (77%) | 7 (54%) | 13 (100%) | 0 |
| CAP | 18 of 36 (50%) | 7 (39%) | 7 (39%) | 4 (22%) | 10 (56%) | 6 (33%) | 15 (83%) | 3 (17%) |
| MO | 8 of 23 (35%) | 3 (38%) | 5 (63%) | 0 | 8 (100%) | 5 (63%) | 8 (100%) | 0 |
Percentages represent proportions of the total population of neurons responsive to the agent. VcPbT, trigeminoparabrachial tract; HT, high threshold; LT, low threshold; WDR, wide dynamic range; sDH, superficial dorsal horn; dDH, deep dorsal horn; β-ALA, β-alanine; HA, histamine dihydrochloride; CQ, chloroquine diphosphate salt; CAP, capsaicin; MO, mustard oil.
*
Responsive neurons showed a decrease in firing rate following injection that met the criteria for an inhibitory response.