P2X(1) receptor subunit immunoreactivity and ATP-evoked fast currents in adult rat dorsal root ganglion neurons

Triple fluorescent staining for P2X(1) and P2X(3) subunits and isolectin I- B4 (IB4) were performed on acutely dissociated rat DRG neurons. Immunoreact ivity for P2X(1) and P2X(3) subunits was present separately or together in DRG neurons. P2X(1) immunoreactivity was present in both IB4-positive and I B4-negative cells. When combining patch-clamp recordings with immunostainin g for the P2X(1) and P2X(3) subunits on single recorded cells, ATP-evoked f ast currents were shown to be present on DRG neurons that have immunoreacti vity for the P2X(3) subunit only, the P2X(1) subunit only, or both P2X(1) a nd P2X3 subunits. These results raised a possibility that,in addition to th e P2X3 receptor subunit, the P2X(1) subunit may also contribute to function al P2X receptors with fast kinetics in DRG neurons. NeuroReport 11:3589-359 2 (C) 2000 Lippincott Williams & Wilkins.