Compared effects of ATP vs adenosine on pulmonary circulation of COPD.

Pulmonary human vasomotor effects of purine nucleotides are unknown. We compared hemodynamic and gasometric effects of ATP vs ADO, using equimolar infusion rate, on 18 chronically hypoxemic COPD patients. ATP infusion (1 and 2 micro Mole per kilo over 20 min) induced pulmonary vasodilation, with a significant decrease of Ppa (-14% -p = 0.025), PVR (-26.6% p = 0.05) and PaO2 (-10.9% p = 0.025). No change was observed when ADO and control solvent were infused. The pulmonary vasodilator effect of infused ATP on COPD patients, seems to be independent of circulating ADO.