EFFECTS OF EARLY SURFACTANT TREATMENT PERSISTING FOR ONE WEEK AFTER LUNG TRANSPLANTATION IN RATS

We investigated whether pulmonary surfactant in rat lung transplants r ecovered during the first week post-transplantation, along with sympto ms of the reimplantation response, and whether this recovery was affec ted by early surfactant treatment. The severity of pulmonary injury wa s varied by transplanting left lungs with 6-h and 20-h ischemia (n = 1 2 and 19, respectively). Half of the transplants were treated by insti llation of surfactant before reperfusion. Lungs from sham operated, an d normal rats (n = 4 and 5, respectively) served as controls. The pulm onary injury severely impaired lung transplant function; 10 of the wor st affected animals died. After 1 wk, symptoms of reimplantation respo nse and properties of pulmonary surfactant were assessed. If untreated , the reimplantation response had almost resolved in the 6-h but not i n the 20-h ischemia group; pulmonary surfactant, however, continued to be deficient in both ischemia groups (low amounts of surfactant phosp holipids and surfactant protein A [SP-A]). Surfactant treatment improv ed the recovery from injury in the 20-h ischemia group resulting in no rmal lung function and amounts of surfactant phospholipids. Amounts of SP-A were not improved by surfactant treatment. In conclusion, early surfactant treatment enhances recovery from transplantation injury and is persistently beneficial for pulmonary surfactant in lung transplan ts.