Lung phosphatidylcholine and fasting in male and female rats.

Lung from male and female rats fasted for 4 days were used. Phospholipid, phosphatidylcholine and its molecular species were analyzed in lungs frm these rats and effects of fasting upon the biosynthesis of phosphatidylcholine in lungs from both sexes were determined using radioactive choline. The molecular species of phosphatidylcholine in both male and female rats did not differ with fasting except the monoenoic species. Incorporation of choline into phosphatidylcholine in both male and female rats significantly increased after fasting, but distribution of radioactivity in phosphatidylcholine yielded similar values in each group. These results suggest that the decrease of saturated phosphatidylcholine content after fasting may not be due to specific change in saturated phosphatidylcholine.