receptor agonist, induced a significant increase
in intracellular calcium compared to baseline (baseline 1.18 ± 0.07 F340/F380 ratio, n=17 vs. BW,
1.37 ± 0.10 F340/F380 ratio, n=17, P<0.001).At higher concentrations the BW723C86-induced
increase in calcium was significantly less than that induced by 100nM BW7the 23C86 (1μM, P<0.01).
In total, 44.1% of submucosal neurones responded to BW723C86 (100nM). However, only 44.5% of
5HT (10uM)-responsive neurones, which itself significantly increased the F340/F380 ratio, also
responded to BW723C86. Furthermore, we identified BW723C86-rsponsive neurones which were also
capsaicin (100nM)-sensitive. Notably, a significant increase in intracellular calcium was also observed
following addition of the 5HT2B receptor antagonist RS127445 (baseline, 0.77 ± 0.06 F340/F380 ratio,
n=12 vs. RS, 0.92 ± 0.05 F340/F380 ratio, n=12, P<0.01).