Distribution of long chain polyenoic acids among phospholipids of mouse testis.

Fatty acid composition of phospholipid (PL) classes was measured in mouse testis. Among the long-chain polyenoic acids (LCPA), 22:6 was found in highest concentration in phosphatidylethanolamine (PE), whereas percentages of 20:4 and 22:5 were not different in PE than in phosphatidycholine. Each PL class had a unique fatty acid composition which was also different from that of triglycerides and cholesteryl esters. Differential metabolisms of 22:5 and 22:6 suggest different roles for these fatty acids in mouse testis. Tissue-specific functions of LCPA in mouse spermatogenesis may be divided between 22:5 and 22:6.