The effects of FK409 on pulmonary ischemia-reperfusion injury in dogs.

FK409 is the first spontaneous nitric oxide (NO) donor known to increase plasma cyclic guanosine 3',5'monophosphate levels. In this study, we evaluated the effect of FK409 on pulmonary ischemia-reperfusion injury in an in situ warm ischemia canine model. Fourteen dogs were divided into two groups, and the FK409-treated group was given 5 micrograms/kg per min FK409. Warm ischemia was induced for 3 h. The arterial partial pressure of oxygen (PaO2), arterial oxygen saturation (SaO2), cardiac output (CO), left pulmonary vascular resistance (L-PVR), and endothelin-I (ET-I) were measured. A histologic study was performed, and polymorphonuclear neutrophils (PMNs) were also counted. The PaO2, SaO2, and L-PVR levels and PMNs after 30 min of reperfusion, ET-I after 2 h of reperfusion, and the 7-day survival rate were significantly (P < 0.05) better in the FK409-treated group than in the control group. The histologic damage was reduced in the FK409-treated group compared to the control group. FK409 appears to have a protective effect in ischemia-reperfusion injury of the lung.