Regulation of Hepatic Phospholipid N-Methylation
The biosynthesis of the major membrane phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), operates via several pathways. The interplay between different reactions is further complicated by the fact that molecular species within each phospholipid class are formed via different routes in a characteristic manner (Åkesson and Sundler, 1977). For several reasons this biosynthetic machinery has been studied extensively in liver. This organ produces phospholipids for the bile and several lipo-protein classes. Thus, the liver has an active phospholipid turnover in a wide variety of pathways. Phospholipid N-methylation was first demonstrated in rat liver by Bremer et al. (1960). Björnstad and Bremer (1966) found that phospholipid methylation was of quantitative importance in liver (see Fig. 1) but not in other organs. The interesting studies of Hirata and Axelrod (1980) have recently stimulated further research on this reaction also in ex-trahepatic tissues.
KeywordsPhospholipid Composition Methylation Rate Arachidonic Acid Release Choline Deficiency Methionine Adenosyltransferase
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- Åkesson, B., 1980, Regulation of phospholipid N-methylation in the hepatocyte, in: Membrane Fluidity: Biophysical Techniques and Cellular Regulation (M. Kates and A. Kuksis, eds.), pp. 419–434, Humana Press, Clifton, N.J.Google Scholar
- Borgström, B., Nordén, Å., Åkesson, B., and Jägerstad, M., 1975, A study of food consumption by the duplicate-portion technique in a sample of the Dalby population, Scand. J. Soc. Med. 3:(Suppl. 10).Google Scholar
- Crang, A. J., and Jacobson, W., 1980, The methylation in vitro of myelin basic protein by arginine methylase from mouse spinal cord, Biochem. Soc. Trans. 8:26.Google Scholar
- Feuer, G., Miller, D. R., Cooper, S. D., de la Iglesia, F. A., and Lumb, G., 1973, The influence of methyl groups on toxicity and drug metabolism, Int. J. Clin. Pharmacol. Ther. Toxicol. 71:13.Google Scholar
- Gwee, M. C. E., and Sim, M. K., 1979, Changes in the concentration of free choline and cephaline-N-methyltransferase activity of the rat maternal and foetal liver and placenta during gestation and of the maternal and neonatal liver in the early postpartum period, Clin. Exp. Pharmacol. Physiol. 6:259.PubMedCrossRefGoogle Scholar
- Mudd, S. H., 1980, Diseases of sulphur metabolism: Implications for the methionine-homocysteine cycle, and vitamin responsiveness, in: Sulphur in Biology, Ciba Foundation Symposium 72, pp. 239–256.Google Scholar
- Stokstad, E. L. R., Chan, M. M.-S., and Watson, J. E., 1981, The metabolic relationship between folic acid, vitamin B12, methionine, and thyroxine, in: The Florida Symposium on Micronutrients in Human Nutrition, University of Florida, Institute of Food and Agricultural Sciences.Google Scholar
- Sundler, R., 19XX, Role of phospholipid head group structure and polarity in the control of membrane fusion, Biomembranes (this volume).Google Scholar
- Yavin, E., and Robert, J., 1979, Dynamics of phospholipids in cultured cells of neural origin, Biochem. Soc. Trans. 7:12.Google Scholar