Lipogenesis in subcutaneous adipose tissue and in oxidative or glycolytic muscles from Angus, Black Japanese x Angus and Limousin steers

摘要

The impacts of the breed and/or anatomical sites on enzyme activities linked to de novo lipogenesis and esterification were investigated. Samples of subcutaneous adipose tissue (SCAT), rectus abdominis (RA) and semitendinosus (ST) muscles were obtained from Limousin, Angus and Black Japanese x Angus steers to assay fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH), malic enzyme (ME) and glycerol-3-phosphate dehydrogenase (G3PDH) activities. FAS (P = 0.03) and G6PDH (P = 0.02) activities expressed per mg of soluble protein were lower in SCAT, RA and ST from Limousin than from Angus and Black Japanese x Angus. Whatever the breed, FAS, ME, G6PDH activities were higher (P < 0.0001), and G3PDH activity was lower (P < 0.0001), in SCAT than in muscles. G3PDH activity was lower (P<0.05) in the oxidative RA than in the glycolytic ST. Significant interaction between breed and anatomical sites were observed for FAS (P = 0.01), G6PDH (P = 0.004) and G3PDH (P < 0.0001) which indicated that (i