We had previously reported the purification of bovine lung natural surfactant-phospholoipd (PNSL)and the assessment of it's surface physical properties in vitro. To observe the clinical effectiveness of PNS-L in vivo, the degree of improvement of thoracic pressure-volume, compliance and histological changes following PNS-L instilation in premature rabbits with respiratory distress syndrome(RDS)were investigated. Rabbits, delivered prematurely by cesarean section at 27 days, treated with PNS-L via tracheostomy, were enrolled the study group. Two control groups were premature RDS rabbits (no treatment with PNS-L)and mature rabbits. We compared the results of thoracic pressure-volume changes during deflation phase and lung compliance changes among PNS-L treated study group and two control groups, and compared the results of aefated lung area ratio (%) on histologic samples among PNS-L treated study group and two control groups by the methods of IBSA-2000. There were significant improvements of thoracic pressure-volume during duflation phase(p<0.001), lung compliance (p<0.01, p<0.005, p<0.001) and increased acrated area histologically (p<0.005)in PNS-L treated study group compared with premature control group. It was suspected that PNS-L had contained the effective survace physical properties as a function of pulmonary surfactant. And improvement of pulmonary ventilatory functions and histological characteristics, were observed in PNS-L treated RDS model in vivo study.
Cesarean Section ; Compliance ; Female ; Humans ; Infant, Newborn* ; Lung ; Lung Compliance ; Pregnancy ; Pulmonary Surfactants ; Rabbits ; Tracheostomy