Catabolism of rat surfactant disaturated phosphatidylcholines during incubation of alveolar lavage materials in vitro at 37 degrees C.
Miles PR; Castranova V; Bowman L
Biochim Biophys Acta 1985 Aug; 836(1):39-44
The catabolism of rat surfactant disaturated phosphatidylcholines was investigated during incubation of rat alveolar lavage materials in-vitro at 37 degrees-C. Male Sprague-Dawley-rats were given intravenous injections of either tritiated palmitate or tritiated choline and sacrificed 22 hours post injection. The amounts of the labeled chemicals in the endogenous surfactant disaturated phosphatidylcholines were determined before and at various times after incubation of alveolar lavage material. The time course of disappearance of endogenous disaturated phosphatidylcholines was linear for approximately 10 minutes post incubation, and the time course for the disappearance of exogenous dipalmitoylphosphatidylcholine was linear for approximately 3 minutes. Catabolism of the disaturated compound was 76 percent complete after 4 hours at 37 degrees-C but only 8 percent complete after 4 hours at 2 degrees-C. The products of the catabolism of choline and palmitate labeled disaturated phosphatidylcholines were free palmitate and water soluble choline derivatives. No lysophosphatidylcholines were found. No correlation between the lactate-dehydrogenase level of the lavage fluid and the amount of disaturated phosphatidylcholine catabolism was found. The authors conclude that the phospholipases present in rat lavage fluid are responsible for the catabolism of disaturated phosphatidylcholines and that the occurrence of these enzymes in the lavage fluid is not due to cellular damage.
NIOSH-Author; Laboratory-animals; Analytical-methods; Bioassays; Cell-metabolism; Alveolar-cells; Lipids; Physiological-response; Enzymatic-effects; Pulmonary-function; In-vitro-studies;
Author Keywords: Lung surfactant; Phosphatidylcholine catabolism; Incubation temperature
P. R. Miles, Physiology Section, ALOSH, 944 Chestnut Ridge Road, Morgantown, WV 26505, U.S.A.
Biochimica et Biophysica Acta