The proportion of P2X1–4 subunit-expressing neurons compared with the total number of NG neurons.

<p>The upper panel shows immunohistochemical staining for P2X1–4 subunits in the maximum cross section of the NG tissues. The lower panel shows that P2X3-IR was the most prevalent neuronal subtype, following by P2X2-IR; P2X4-IR had the lowest prevalence. *<i>p</i><0.05.