Frequency of response to purinergics in ORNs and sustentacular cells. Shown are the percentages of ATP-sensitive ORNs (A; identified by odor responsiveness; n = 14) and SCs (B; identified by location and lack of odor response; n = 122) that also had increases in [Ca2+]i evoked by nonselective purinergic receptor agonists (ATP, ATPγS), P2Y-selective agonists (UTP, ADP, MeSADP), and P2X-selective agonists (βγ-MeATP). The concentration for all purinergics was 10 μM.