The labelling of surfactant phosphatidylcholine and disaturated phosphatidylcholine was studied in 19-31-days-old lambs. Following the placement of small bore tracheal catheters, the animals were given radioactivity labelled palmitic acid and/or choline by intravenous injection and multiple samples were recovered from the distal airways of each animal via a small catheter. The specific activities of the phosphatidylcholine and/or disaturated phosphatidylcholine were measured in these samples of surfactant. The labelled phospholipids accumulated in the samples of surfactant in a linear fashion; the mean time required to reach maximal specific activities in phosphatidylcholine and saturated phosphatidylcholine with either palmitic acid or choline as precursor was 28 h. Subsequently the specific activities of the labelled phospholipids from the surfactant samples decreased semi-logarithmically. The mean t 1/2 for phosphatidylcholine and disaturated posphatidylcholine labelled with radioactive palmitic acid was 35 h. The saturated phosphatidylcholine labelled with radioactive choline had a t 1/2 of 251 h. The results demonstrate that surfactant labelling studies can be done by multiple sampling of single large animals.
|Original language||English (US)|
|Number of pages||14|
|Journal||Journal of Developmental Physiology|
|State||Published - Dec 1 1979|
ASJC Scopus subject areas
- Developmental Biology