Abstract

The effects of ethanolamine, choline, and different fatty acids on phospholipid synthesis via the CDP-ester pathways were studied in isolated rat intestinal villus cells. The incorporation of [14C]glucose into phosphatidylethanolamine was stimulated severalfold by the addition of ethanolamine and long-chained unsaturated fatty acids, while the addition of lauric acid inhibited the incorporation of radioactivity into phosphatidylethanolamine. At concentrations of ethanolamine higher than 0.2 mM, phosphoethanolamine accumulated, but the concentrations of CDP-ethanolamine and the incorporation of radioactivity into phospatidylethanolamine did not increase further. The incorporation of [14C]glucose into phosphatidylcholine responded in a way similar to that of phosphatidylethanolamine, except that a 10-fold higher concentration of choline was required for maximal stimulation. CCC inhibited the incorporation of choline into phosphatidylcholine. In contrast with hepatocytes, villus cells did not form phosphatidylcholine via phospholipid N-methylation. The data indicate that, in intestinal villus cells, the cytidylyltransferase reactions are rate limiting in the synthesis of phosphatidylethanolamine and probably also of phosphatidylcholine. The availability of diacylglycerol and its fatty acid composition may also significantly affect the rate of phospholipid synthesis.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.