Fig. 7.

Calcium transients activated by ATP and its breakdown products in trigeminal cells. a Representative traces recorded from cultured trigeminal neurons (average of 10 traces). Application of adenine nucleotides (ATP, ADP, and AMP) or adenosine (Ado) solutions (all in 10 μM) for 2 s to trigeminal ganglion cells loaded in fluo 5 μM 3-AM. Neurons were distinguished from other cell types due to Ca²⁺ responses induced by potassium depolarization (50 mM KCl for 2 s). Notice neuronal responses to ATP and ADP, but not to AMP and Ado. b Representative Ca²⁺ transients from satellite glial cells (SGC, n = 10 cells) activated by ATP and ADP. c Histograms showing percent of neurons responding to ATP, ADP, AMP, and adenosine (total number 173 cells). d Histograms showing percent of SGCs responding to ATP, ADP, AMP, and adenosine (total number 282 cells). Mean ± SEM. *p < 0.05 (determined by the Mann-Whitney test)