Conversion of choline to phosphatidylcholine in the isolated-ventilated-perfused neonatal rabbit lung.
The isolated-ventilated-perfused neonatal rabbit lung model was used to study pulse dosed 14C-choline incorporation into 14C-phosphatidylcholine (PC) and 14C-disaturated phosphatidylcholine (DSPC). 14C-PC and 14C-DSPC synthesis were linearly dependent upon perfusion time to 30 min and upon the pulse dose of 14C-choline of 20-250 nmol at both 10 and 30 min of perfusion. 2-3% of the pulse-dosed choline was taken up by the lung. The water-soluble metabolites of choline found in lung after 10-30 min of perfusion were: choline, 50-60%; betaine 2.4-3.0%; phosphorylcholine, 26-41%, and CDP-choline, trace-10%. 1-day-old perfused lungs incorporated pulse-dosed 14C-choline into 14C-PC and 14C-DSPC at slightly higher rates than at 10 days old. Newborn rabbits receiving an intraperitoneal injection of 0.1 mg dexamethasone/100 g body weight 16 and 22 h prior to perfusion incorporated significantly more 14C-choline into 14C-PC and 14C-DSPC than saline-injected controls.
D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D002794:Choline / Q000008:administration & dosage / Q000378:metabolism*; D003907:Dexamethasone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D008168:Lung / Q000187:drug effects / Q000378:metabolism*; D010477:Perfusion; D010713:Phosphatidylcholines / Q000378:metabolism*; D011817:Rabbits; D013997:Time Factors
D010713:Phosphatidylcholines; D003907:Dexamethasone; D002794:Choline