Effects of testosterone on triglyceride levels and fatty acid composition in the liver and serum of the rat.

Triacyglycerol content and fatty acid composition has been determined in the liver and in the serum of normal, castrated and testosterone-treated rats. Most variations were found in UNS/SAT ratio, which were referred to an action of the hormone on the delta 5-delta 6-delta 9 desaturases. Results concerning the behaviour of delta 9 desaturase suggest that either different isoenzymes are involved or that a single enzyme undergoes a different regulation according to the substrate involved.