Purinergic Signaling Pathway in Human Olfactory Neuronal Precursor Cells

Figure 9

Contribution of the ionotropic or the metabotropic pathway to the purinoceptor-mediated response to ATP in precursor cells of the hOE. Ionotropic P2X receptors induce an extracellular Ca²⁺ influx when stimulated, while G-protein coupled P2Y receptors induce release of Ca²⁺ from the intracellular stores through IP3 stimulation. The contribution of Ca²⁺ influx through P2X receptors in hOE precursors was determined by perfusing cells with a Ca²⁺-free solution (a) () and stimulating them with ATP. The metabotropic P2Y pathway was blocked using NEM, a G-protein uncoupler (b) (). The former diminished the response to ATP by 10%, and NEM blocked the response by 90%. Data represent the and were compared with a Student test. .

(a)

(b)