P2RX7 and autosomal dominant polycystic kidney disease: Consistent with the data in MDCK cells, in a zebrafish model of ADPKD (morpholino induced knockdown of Pkd2), a P2X7 antagonist (oxidized ATP) markedly reduced the cystic dilatation and peritubular oedema in pronephric ducts compared to the control (no treatment) or to a P2X7 agonist (Bz-ATP) (Chang et al., 2011).