Interazioni tra platelet activating factor (PAF), ossido d’azoto (NO) ed endotelina-1 (ET-1) sul circolo polmonare e sistemico e sulla meccanica respiratoria nel suino

In 9 anaesthetized and mechanically ventilated Large White pigs, we analyzed the effects of Platelet Activating Factor (PAF 50 ng/kg i.v.) on circulatory and mechanical respiratory parameters, before and after administration of NG-nitro-L-arginine methyl ester (L-NAME, 5 mg/kg i.v.), a blocker of nitric oxide synthase and Bosentan (15 mg/kg i.v.), a blocker of endothelin-1 (ET-1) receptors. Our results showed that PAF increased pulmonary (PAPM) and decreased systemic (PAM) arterial pressures; these effects were reduced in animals pretreated with L-NAME and Bosentan. The pretreatment with these two antagonists avoided the increse in resistances (Rrs) and the decrease in passive compliance (Crs) of the respiratory system due to PAF administration.