title: Synthetic lung surfactant reduces alveolar-capillary protein leakage in surfactant-deficient rabbits.
abstract: OBJECTIVE
  Alveolar-capillary leakage of proteinaceous fluid impairs alveolar ventilation and surfactant function and decreases lung compliance in acute lung injury. We investigated the correlation between lung function and total protein levels in bronchoalveolar lavage fluid (BALF) of ventilated, lavaged surfactant-deficient rabbits treated with various clinical and synthetic lung surfactant preparations.
  
  
  METHODS
  109 ventilated, young adult New Zealand White rabbits underwent lung lavage to induce surfactant-deficiency (PaO2 <100 torr in 100% O2), were treated with a clinical surfactant or a synthetic surfactant preparation with surfactant protein B (SP-B) and/or surfactant protein C (SP-C) analogs, and mechanically ventilated for 120 min. Total protein levels in postmortem BALF were correlated with arterial PO2 (PaO2) and dynamic lung compliance values at 120 min post-surfactant treatment.
  
  
  RESULTS
  Repeated lung lavages decreased mean PaO2 values from 540 to 58 torr and lung compliance from 0.64 to 0.33 mL/kg/cm H2O. Two hours after surfactant therapy and mechanical ventilation, mean PaO2 values had increased to 346 torr and lung compliance to 0.44 mL/kg/cm H2O. Eighty-six rabbits (79%) responded to surfactant therapy with an increase in PaO2 to values >200 torr. Fourteen non-responders received inactive surfactant preparations. BALF protein levels were inversely correlated with PaO2 and lung compliance (P < .001). Surfactant preparations containing both SP-B and SP-C proteins or peptide analogs outperformed single protein/peptide preparations.
  
  
  CONCLUSIONS
  Clinical and synthetic surfactant therapy reduces alveolar-capillary protein leakage in surfactant-deficient rabbits. Surfactant preparations with both SP-B and SP-C (analogs) were more efficient than preparations with SP-B or SP-C alone.
authors.affiliation: 1Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, California, USA.
authors.forename: Rohun
authors.initials: R
authors.lastname: Gupta
authors.forename: José M
authors.initials: JM
authors.lastname: Hernández-Juviel
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Waring
authors.forename: Frans J
authors.initials: FJ
authors.lastname: Walther
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D008168:Lung / Q000187:drug effects / Q000378:metabolism; D008170:Lung Compliance / Q000187:drug effects; D010100:Oxygen / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D011506:Proteins / Q000378:metabolism*; D011650:Pulmonary Alveoli / Q000187:drug effects* / Q000378:metabolism; D011663:Pulmonary Surfactants / Q000494:pharmacology*; D011817:Rabbits; D012121:Respiration, Artificial / Q000379:methods
chemical_list: D010455:Peptides; D011506:Proteins; D011663:Pulmonary Surfactants; D010100:Oxygen
keywords: alveolar-capillary leakage; bronchoalveolar lavage fluid; lung function; protein; surfactant