Influence of selective inhibitors of phosphodiesterase 3 and 4 on cough and airway reactivity.

As the administration of many antitussive drugs is often associated with adverse effects, new alternatives are evaluated in experimental and clinical conditions. The aim of this study was to assess the influence of selective inhibitors of PDE3 (cilostazol) and PDE4 (citalopram) on cough and airway reactivity. The number of cough efforts, specific airway resistance, in vitro airway reactivity, and differential blood cells count were measured in healthy and in ovalbumin-sensitized guinea pigs before and after administration of cilostazol or citalopram (1 mg/kg). Cilostazol significantly suppressed citric acid induced cough only in healthy guinea pigs, whereas citalopram in both healthy and ovalbumin-sensitized animals. Both PDE inhibitors decreased in vivo and in vitro airway reactivity to histamine and the count of monocytes and neutrophils, confirming their anti-inflammatory potential. Administration of selective PDE3 and PDE4 inhibitors may influence cough and airway reactivity in the model of ovalbumin-sensitized guinea pigs.