Figure 1.

Dopamine attenuates purinergic signaling in type II cells. (A) Representative trace showing the reduction of the intracellular Ca²⁺ ([Ca²⁺]_i) response to UTP (100 µM) during application of DA (10 µM) in type II cells (blue trace); contrast the type I cell (red trace) which only responded to high K⁺. (B) Summary data of UTP-evoked integrated [Ca²⁺]_i (nM∙S) response before, during, and after DA perfusion (n = 8 dishes/group, 10–25 cells sampled per dish). In (B) 221 of the 298 type II cells showed a reduction in the UTP response in the presence of DA. (C) Mean duration (s) of the UTP-evoked [Ca²⁺]_i response in type II cells before, during, and after DA (10 µM) perfusion. Data were analysed using a one-way repeated measures analysis of variance (ANOVA) followed by Tukey’s post hoc test; ** signifies a p value of < 0.01. Values are means ± S.E.M.; n = 8 dishes.