The amount of the settled surfactant dipalmitoylphosphatidylcholine (DPPC) in the heart of rats does not correlate with decompression illness.

Abstract

INTRODUCTION: The lung surfactant dipalmitoylphosphatidylcholine (DPPC) settles on the luminal aspect of blood vessels to form active hydrophobic spots (AHS). The nanobubbles that develop at these spots are gas micronuclei from which decompression bubbles expand upon decompression. Variability between "bubblers" and "non-bubblers" is derived from the variability in the AHS. We expected that the level of DPPC in the heart would correlate with the severity of decompression illness (DCI). METHODS: Thirty-six rats were exposed to 8 bar for 32 minutes. RESULTS: After decompression, they were examined for DCI and defined as non-DCI rats (ND, n=18), DCI-inflicted rats (DCI, n=13), and dead rats (DEATH, n=5). The DPPC concentration in the hearts (mg/g) was 2.97 ± 0.56 SD for ND, 2.87 ± 0.62 SD for DCI, and 2.81 ± 0.46 SD for DEATH. DISCUSSION: There was no significant difference between the three groups. The results are discussed, and a further study to explore the correlation between bubbling and heart DPPC is suggested.