Interferenza tra ossido d’azoto (NO) e canali del potassio ATP-sensibili sulla fatica diaframmatica nel suino

In 6 anaesthetized and mechanically ventilated Large White pigs we analyzed the interference between nitric oxide (NO) and K+ATP channels on diaphragmatic activity. The pigs were treated initially with NG-nitro-L-arginine methyl ester (L-NAME, 5 mg/kg i.v.), to block endogenous NO, and subsequently with Cromakalim (80 microg/kg i.v.) to open K+ATP channels. L-NAME increased systemic arterial pressure (PAM) and vascular resistances (RVS), while Cromakalim decreased both PAM and RVS. Cromakalim caused also an impairment of diaphragmatic activity, showing that when endogenous NO is blocked, also the K+ATP channels activity is altered.