Figure 5.

Ca²⁺ responses in the myenteric plexus in the presence of tetrodotoxin (TTX). (A) Neuronal response to veratridine (10 μM) added to the bath (arrow). Note the absence of responses to veratridine in the presence of TTX. (B) Neuronal response to KCl (75 mM) added to the bath (arrow). Note that the response is preserved in the presence of TTX. (C) Quantification of baseline (left panel) and KCl-induced Ca²⁺ responses and dynamics in the different regions of the gut in the absence of luminal contents and in the presence of TTX (other panels). n=2 per group and per intestinal segment (n=6 mice total); The inter-region variability and specificity of Ca²⁺ dynamics were virtually identical in the presence of TTX (compare to Fig. 4).