Bradykinin evokes a Ca2+-activated chloride current in non-neuronal cells isolated from neonatal rat dorsal root ganglia

1. We have studied the effect of bradykinin (Bk) on fibroblast-like satellite (FLS) cells isolated from cultures of neonatal rat dorsal root ganglia (DRG). 2. In voltage-clamped FLS cells Bk evoked an inward current response that was concentration dependent with a half-maximal concentration of 2 nM. 3. In indo-1 AM-loaded FLS cells Bk evoked a rise in intracellular Ca2+ that was concentration dependent with a half-maximal concentration of 1 nM. 4. The FLS cells still, produced an inward current in response to Bk in the absence of extracellular Ca2+ but the response was inhibited if the intracellular concentration of EGTA was increased from 0.5 to 5 mM, which suggests that the inward current was dependent on the release and subsequent rise of intracellular Ca2+. 5. The reversal potential of the Bk-induced inward current was consistent with the current being due to an increase in Cl- conductance and shifted in a Nernstian manner when the intracellular Cl- concentration was reduced. 6. The inward current response to Bk was blocked by the B-2 receptor antagonist HOE-140, which indicates that the response was due to activation of B-2 receptors. 7. The data suggest that Bk evokes a rise in intracellular Ca2+ and activation of a Ca2+-activated Cl- conductance in the FLS cells and raise the possibility that FLS cells contribute to the proinflammatory effects of Bk in DRG.