Mario Cazzola1, Maria Gabriella Matera2. 1. Unit of Respiratory Clinical Pharmacology, Department of Systems Medicine, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy. Electronic address: mario.cazzola@uniroma2.it. 2. Unit of Pharmacology, Department of Experimental Medicine, Second University of Naples, Naples, Italy.