The effect of tissue region on visceral afferent mechanosensitivity and chemosensitivity
| All tissues | Sigmoid colon | Rectum | |
|---|---|---|---|
| Mechanosensitivity VFH (g) | Firing rate spikes 2 s−1 probe Proportion responders | Firing rate spikes 2 s−1 probe Proportion responders | Firing rate spikes 2 s−1 probe Proportion responders |
| 0.07 | 8.8±1.8 7/13 (54%) | 9.1±1.6 4/8 (50%) | 7.8±7.3 2/3 (67%) |
| 0.4 | 17.8±2.7 12/13 (92%) | 20.6±3.7 7/8 (88%) | 15.7±5.2 3/3 (100%) |
| 2 | 23.7±3.3 11/11 (100%) | 25.4±4.6 7/7 (100%) | 24.2±4.4 3/3 (100%) |
| Chemosensitivity | Δ Firing rate spikes 20 s−1 Proportion responders | Δ Firing rate spikes 20 s−1 Proportion responders | Δ Firing rate spikes 20 s−1 Proportion responders |
| Bradykinin | 49.1±8.6 24/39 (62%) | 57.7±14.7 12/23 (52%) | 38.3±14.9NS 5/7 (71%) |
| ATP | 30.3±5.4 23/26 (88%) | 32.8±7.9 14/16 (88%) | 28.5±13.5NS 4/4 (100%) |
Table illustrating single unit responses to VFH probing at 0.07, 0.4 and 2 g, bradykinin or ATP in tissues from different tissue regions. The data were analysed for tissue from cancer resections only. Mean±SEM;p>0.05; paired t-test.
NS, not significant; VFH, von Frey hair.