title: Functional impairment of bronchoalveolar lavage phospholipids in early Pneumocystis carinii pneumonia in rats.
abstract: Surfactant abnormalities may contribute to the impairment of gas exchange observed in Pneumocystis carinii pneumonia. Analysis of rat bronchoalveolar lavage (BAL) lipid extracts from normal controls, steroid controls, trimethaprim-sulfamethoxazole (TMP-SMX) controls, TMP-SMX/P. carinii pneumonia controls, and P. carinii pneumonia animals reveal similar total phospholipid and total protein levels. However, there was a marked reduction in phosphatidylglycerol (PG) from the BAL of P. carinii pneumonia rats as compared with control animals, with a decrease from 4.91 +/- 1.29 nmol/mg protein to 0.46 +/- 0.57 nmol/mg protein (p<0.05) and a decrease, as a percent of total phospholipids, from 7.7% +/- 0.88% to 0.91% +/- 0.59% (p<0.001). Furthermore, in vitro surface activities of BAL lipid extracts from control and P. carinii pneumonia rats revealed minimum surface tension increases from 9.38 +/- 1.71 mN/m in controls to 16.36 +/- 0.83 mN/m in P. carinii pneumonia rats (p<0.05) and likewise maximum surface tension increases from 22.14 +/- 4.34 mN/m to 38.57 +/- 2.07 mN/m (p<0.01). Of interest, the surface activity of PG-deficient P. carinii pneumonia BAL lipid extracts is completely restored to that of normal controls by the addition of exogenous PG. These findings suggest that a functionally abnormal surfactant occurs in P. carinii pneumonia and that this may account, in part, for the impairment of gas exchange observed in this disorder.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Indiana University School of Medicine, Indianapolis, USA.
authors.forename: T H
authors.initials: TH
authors.lastname: Su
authors.forename: V
authors.initials: V
authors.lastname: Natarajan
authors.forename: D L
authors.initials: DL
authors.lastname: Kachel
authors.forename: M A
authors.initials: MA
authors.lastname: Moxley
authors.forename: W J
authors.initials: WJ
authors.lastname: Longmore
authors.forename: W J
authors.initials: WJ
authors.lastname: Martin
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D005260:Female; D007165:Immunosuppression Therapy; D008055:Lipids / Q000032:analysis; D010715:Phosphatidylglycerols / Q000172:deficiency / Q000494:pharmacology; D010743:Phospholipids / Q000032:analysis / Q000502:physiology*; D011020:Pneumonia, Pneumocystis / Q000503:physiopathology*; D051381:Rats; D011917:Rats, Inbred Lew; D013997:Time Factors
chemical_list: D008055:Lipids; D010715:Phosphatidylglycerols; D010743:Phospholipids