TABLE 2.
CALCULATED PERCENT VOLUME RECOVERIES AT LOW TRANSPULMONARY PRESSURES AFTER TRACHEAL INSTILLATION OF SURFACTANTS PLUS INHIBITORS INTO SURFACTANT-DEFICIENT EXCISED RAT LUNGS
| Lung Volume Recovery Percentage at Various Deflation at Various Transpulmonary Deflation Pressures (cm H2O)
|
||||
|---|---|---|---|---|
| Surfactant Mixture | 4 | 6 | 8 | 10 |
| DEPN-8 + 1.5% SP-B/C | 95.9 ± 3.0 | 94.6 ± 3.5 | 94.1 ± 4.7 | 98.3 ± 2.6 |
| CLSE | 95.9 ± 9.5 | 94.5 ± 6.7 | 93.7 ± 5.6 | 94.3 ± 5.0 |
| DEPN-8 + 1.5% SP-B/C + PLA2 | 93.2 ± 6.9* | 92.2 ± 5.4* | 93.3 ± 4.5* | 94.7 ± 4.0* |
| CLSE + PLA2 | 54.4 ± 6.1 | 59.8 ± 4.6 | 66.9 ± 4.3 | 72.3 ± 4.3 |
| DEPN-8 + 1.5% SP-B/C + LPC | 82.0 ± 1.1† | 81.2 ± 2.7† | 83.8 ± 1.9† | 84.8 ± 1.8† |
| CLSE + LPC | 64.7 ± 2.9 | 67.7 ± 3.3 | 71.8 ± 3.0 | 69.1 ± 2.1 |
| DEPN-8 + 1.5% SP-B/C + BSA | 53.7 ± 1.2 | 49.0 ± 1.0 | 55.6 ± 4.7 | 56.7 ± 2.9 |
| CLSE + BSA | 56.0 ± 2.9 | 51.9 ± 2.0 | 54.6 ± 2.5 | 55.4 ± 3.2 |
Definition of abbreviations: BSA, bovine serum albumin; CLSE, calf lung surfactant extract; LPC, C18:1 lysophosphatidylcholine; PLA2, phospholipase A2; SP, surfactant protein.
Percent recovery is calculated by the equation 100(Vsur − Vdef)/(Vnorm − Vdef), where Vnorm is the volume of the freshly excised lungs, Vdef is the volume of the lavaged surfactant-deficient lungs, and Vsur is the volume after surfactant instillation at the pressure of interest. PLA2 (0.1 U/ml), C18:1 LPC (15% by weight relative to lipid), or BSA (3 mg/ml) were incubated with surfactants in vitro before instillation into surfactant-deficient rat lungs (see Materials and Methods). Data are mean ± SEM for n = 3–6. Complete P–V deflation curves for the four cases in the table are shown in Figures 1–4, respectively.
Different from CLSE + PLA2, P < 0.0067.
Different from CLSE + LPC, P < 0.05.