[Effect of an essential fatty acids free diet on the lipidic composition of rat testicles (author's transl)].

The effect of a fat free diet on the fatty acid composition and histological changes of the testis of old rats was studied to investigate the possible function of docosa-4,7,10,13,16-pentaenoic acid in rat testicles. The lipidic composition, the fatty acid composition, the conversion of docosa-7,10,13,16-tetraenoic acid to arachidonic acid and the activity of the 6-desaturase were determined during the different periods in which the rats received a fat free diet. Comparatively, the changes in the fatty acid composition of the liver were also studied. Only the liver showed a change in the triglyceride content during the first month of treatment, and it regained its normal values afterwards. Both liver and testis changed the fatty acid composition. An increase of the acids of the oleic series and a decrease of the components of the linoleic series were shown. These changes were similar to the ones provoked by an essential fatty acid deficient diet on young animals. The amount of docosa-4,7,10,13,16-pentaenoic acid was very little changed. No significant change was shown either in the retroconversion of docosa-7,10,13,16-tetraenoic acid to arachidonic acid. However, the 6-desaturase activity of the testis was enhanced by the fat deficient diet. The possibility that arachidonic acid in the adult rat is mainly supplied by linoleic acid and not by the retroconversion of docosa-4,7,10,13,16-pentaenoic acid is discussed.