Fig. 5. LC activation triggers afferent firing via a calcium-dependent mechanism.

(A) Exemplar traces recorded in a Meissner afferent in response to LC activation by voltage clamp with a cesium-based internal solution to quench potassium efflux (control), following the removal of extracellular Ca²⁺ and the addition of 300 μM Cd²⁺ to block voltage-activated calcium channels (No Ca²⁺) and upon reintroduction of calcium and removal of Cd²⁺ (Wash). V_LC, voltage step stimulus applied to the LC; I_LC, current response in the LC; V_aff, extracellular voltage and APs in the afferent. (B) Quantification of the effect of calcium removal on LC-induced afferent firing. Lines connect data from the same afferent (n = 5 afferents). The difference between control and wash was not significant (P = 0.6856). Friedman test with Dunn’s correction for multiple comparisons.