Phosphodiesterase (PDE) inhibitors may have significant clinical benefit in respiratory diseases associated with inflammation. The aim was to evaluate effects of selective PDE7 inhibitor (BRL50481) on citric acid induced cough,
Tested drugs were administered intraperitoneally to male guinea pigs once daily for 7 days either vehicle 10% DMSO (dimethyl sulfoxide) 3 ml/kg (as control) or BRL50481 1 mg/kg. Double chamber whole body plethysmograph was used for evaluation of citric acid (0.6 M) induced cough and specific airway resistance. Organ bath method was used for measurement of tracheal and lung tissue strips contractions evoked by cumulative doses (10-8 - 10-3 mol/L) of acetylcholine (ACH) and histamine (HIS).
In healthy guinea pigs we did not observe significant effect of tested drug BRL50481 on
Our results suggest that PDE7 inhibitors have stronger anti-inflammatory effect compared to its direct effect on smooth muscle and cough.