Expression of P2Y receptors in cell lines derived from the human lung

Northern blotting experiments have been performed with RNA extracted from several cell lines derived from the human lung in order to detect P2Y 1 , P2Y 2 , P2Y 4 and P2Y 6 mRNA. We have investigated the 1HAEo− and 16HBE14o− epithelial cell lines derived from the airway epithelium, the A549 cell line displaying properties of type II alveolar epithelial cells, the CALU‐3 serous cells, the 6CFSMEo− submucosal cells and the HASMSC1 airway smooth muscle cells. We have also evaluated one pancreatic epithelial cell line called CFPAC‐1. These experiments revealed that P2Y 2 and P2Y 6 mRNA are co‐expressed in the 1HAEo−, 16HBE14o− and A549 epithelial cell lines. The CFPAC‐1 pancreatic cell line was strongly positive for the P2Y 2 receptor. No signal was obtained for the P2Y 1 and P2Y 4 receptors. We have then performed RT–PCR experiments with specific oligonucleotides of these last two P2Y receptors with the RNA used for the Northern blotting experiments. P2Y 4 mRNA was detected in five cell lines: 1HAEo−, 16HBE14o−, 6CFSMEo−, HASMSC1 and CFPAC‐1. P2Y 1 mRNA was only detected in the CALU‐3 cell line. Inositol trisphosphates assays have identified a response typical of the P2Y 2 receptor in the 1HAEo− and the 16HBE14o− airway epithelial cell lines which co‐express P2Y 2 and P2Y 6 mRNA. By contrast, the 6CFSMEo− submucosal cells expressed a UTP‐specific response which displayed pharmacological characteristics compatible with the human P2Y 4 receptor: in particular, there was no response to UDP or ATP and the UTP effect was totally inhibited by pertussis toxin.British Journal of Pharmacology (1999) 127 , 562–568; doi: 10.1038/sj.bjp.0702560