Lubricating recovery of damaged pleural mesothelium: effect of time and of phosphatidylcholines.

Effect of time and phosphatidylcholines (PCs) on lubrication of damaged mesothelium has been investigated. Marked increase in coefficient of kinetic friction ( μ ) of pleural specimens after mesothelial blotting and rewetting decreased by 23.4 ± 3.5%, 41.8 ± 3.8%, and 40.5 ± 2.7% after 30 min, 1 h, and 2 h. Hence, damaged mesothelium is able to partially reset lubricating molecules on its surface. Increase in μ of post-blotting Ringer 2 h after addition of unsaturated PCs (3 mg/ml) decreased a little more than after 2 h Ringer. Effects of unsaturated and saturated PCs were similar, contrary to expectation raised by their different percentage in pleural and alveolar lavage. Effect of PCs did not increase at 6 mg/ml, and was nil at 0.4 mg/ml. Increase of μ after short phospholipase treatment decreased by 45.9 ± 2.0% after 2 h Ringer, and a little more after addition of unsaturated or saturated PCs. Hence, PCs, as other phospholipids, have a small effect, likely because of difficulty in resetting their relationships with main lubricating molecules. [ABSTRACT FROM AUTHOR]