THE PRESENT INVENTION RELATES TO SOLUBLE GUANYLATE CYCLASE (SGC) AND TO PHOSPHODIESTERASES (PDES) AND THE PHARMACOLOGY OF SGC STIMULATORS, SGC ACTIVATORS AND PDE INHIBITORS. MORE PARTICULARLY, THE INVENTION RELATES TO THE USE OF SGC STIMULATORS AND SGC ACTIVATORS IN COMBINATION WITH PDE5 INHIBITORS FOR PREPARATION OF MEDICAMENTS FOR THE TREATMENT OF CYSTIC FIBROSIS (CF).