Journal of Applied Physiology, Vol 39, Issue 5 780-787, Copyright © 1975 by American Physiological Society
Oxygen-induced changes in pulmonary phospholipids in the rat
M. Valimaki, T. T. Pelliniemi and J. Niinikoski
The composition and synthesis of alveolar and lung tissue phospholipids
were investigated in normal and oxygen-poisoned rat lungs. Sixty-hour
exposure to oxygen increased the total amount of phospholipids in the
endobronchial extracts and lung tissue. Phosphatidyl glycerol was
identified in both endobronchial extracts and lung tissue. The amount of
unsaturated fatty acids in surfactant lecithin and phosphatidyl glycerol
was slightly increased in oxygen-poisoned lungs whereas the composition of
phospholipids in the endobronchial extracts was not affected by oxygen.
After intraperitoneal administration of [32P]phosphate the specific
activities of surfactant lecithin and phosphatidyl glycerol were clearly
lower in oxygen-treated animals whereas the specific activities of lung
tissue lecithin and phosphatidyl glycerol remained unaffected. The
synthesis of lecithin from [14C]methionine through N-methyltransferase
pathway was markedly depressed in lung slices but increased in liver tissue
taken from oxygen-poisoned rats and incubated under oxygen indicating a
difference between lung and liver methyltransferase enzymes. In conclusion,
the present work suggests impaired synthesis and removal of alveolar
phospholipids in oxygen-poisoned rats.
