Purinergic P2x Receptors Are Present And Functional In Conjunctival Goblet Cells

Purpose: P2X receptors are activated by nucleotides such as ATP. Upon activation, the P2XRs become permeable to calcium which is a potent stimulator of mucin secretion in goblet cells. P2X7 receptors are capable of creating pores together with pannexin 1-3 hemichannels allowing flux of larger molecules and cell death in certain tissues. The purpose of this study was to investigate the presence and function of P2XRs in conjunctival goblet cells (CGCs).Methods: Goblet cells were cultured from pieces of rat conjunctiva. Presence of P2X1-7 receptor and pannexin mRNA transcript expression and protein was determined by RT-PCR, western blotting (WB) analysis, and immunofluorescence (IF) microscopy. To study receptor function, CGCs were incubated with the ratiometric fluorescent dye Fura 2-AM, stimulated with ATP or the P2X7-specific ATP analogue BzATP, and intracellular [Ca 2+]([Ca 2+] i) measured …