Fig. 5.

Role of extracellular Ca²⁺ in the positive interaction of TRPA1 and TRPV1 channels. A: experimental records illustrating the positive interaction of TRPA1 and TRPV1 channels during control in a jugular neuron (27.4 pF). B: positive interaction was completely abolished after the same neuron was perfused by Ca²⁺-free ECS for 10 min. C: positive interaction returned after the same neuron was perfused by regular ECS again for 20 min. D: group data of the responses (n = 16) when neurons were perfused with regular ECS (control) and Ca²⁺-free ECS, respectively. E: in 4 of these 16 neurons, group data were also obtained after the Ca²⁺-free ECS was washed out. Data are means ± SE. *P < 0.05, significantly different from the response to Cap+AITC.