Figure 6. Pharmacological analysis of NCX activity in putative nociceptive cutaneous DRG neurons.

A, high K⁺ evoked Ca²⁺ transients in putative nociceptive cutaneous neurons before and in the presence of increasing concentrations of the NCX3 selective blocker KB-R7943 (top trace), the NCX1 selective blocker SEA0400 (middle trace) and a second NCX1 selective blocker SN-6 (bottom trace). B, pooled concentration–response data from neurons treated with KB-R7943 (n = 25), SEA0400 (n = 11) or SN-6 (n = 10). Data were analysed as an increase in transient duration (T₅₀) relative to the transient duration in the presence of vehicle. KB-R7943 data were well fitted with a Hill equation, yielding an E_max = 107.25 ± 20.36 s and EC₅₀ = 0.045 ± 0.01 μm. C, the maximal change in transient duration in the presence of blocker was analysed as a percentage of the total block of NCX activity represented by the maximal change in duration observed in Na⁺-free bath. Data for each blocker was pooled and plotted.