本试验旨在研究不同饲粮能量水平对乌金猪脂肪组织脂类合成代谢相关基因表达的影响.选取体重约15 kg的乌金猪54头,随机分为3组,每组3个重复,每个重复6头猪,分别饲喂消化能为11.74(低能组)、12.89(中能组)和14.22 MJ/kg(高能组)的3种饲粮.分别在体重为30、60和100kg时屠宰,测定胴体脂肪率,取皮下脂肪组织,荧光定量PCR检测脂肪合成代谢相关酶和因子[乙酰辅酶A羧化酶(ACC)、脂肪酸合成酶(FAS)和固醇调节元件结合蛋白lc(SREBP-lc)]及脂肪酸转运因子[脂肪细胞型脂肪酸结合蛋白(A-FABP)]表达水平.结果表明:1)体重为60和100kg时,乌金猪脂肪率随饲粮能量水平的升高而极显著升高(P＜0.01);2)体重为30和100kg时,与中能组相比,高能组猪ACC、FAS和SREBP-1c的表达水平显著下降(P＜0.05),体重60kg时表达水平显著提高(P＜0.05);3)体重为30和100kg0时,AFABP表达水平随饲粮能量水平增加显著提高(P＜0.05),体重60kg时表达水平随饲粮能量水平增加而显著降低(P＜0.05).结果提示:在体重为60 kg时,高能量饲粮显著促进乌金猪脂肪组织脂类合成代谢相关基因(ACC、FAS、SREBP-1c)的表达,显著抑制脂肪酸转运相关基因(AFABP)的表达,降低了脂肪酸转运,从而使脂肪组织的游离脂肪酸的从头合成增加和对外源脂肪酸的摄取降低.%The aim of the study was to investigate the effects of dietary energy level on expression of lipid anabolism related genes in adipose tissue of Wujin pigs. Fifty-four Wujin pigs with the body weight of 15 kg were randomly assigned into 3 groups with 3 replicates per group and 6 heads in each replicate. Pigs in low digestive energy group ( group LDE), middle digestive energy group ( group MDE) and high digestive energy group ( group HDE) were fed diets with three digestive energy levels, which were 11.74, 12.89 and 14.22 MJ/kg, respectively. At the body weight of 30, 60 and 100 kg, pigs were slaughtered to determine the fat percentage. The subcutaneous adipose tissue was collected for the analysis of expression levels of lipid anabolism related genes [acetyl-CoA carboxylase (ACC), fatty acid synthetase (FAS) and sterol regulatory element-binding protein lc (SREBP-lc)]and fatty acid transport factor [adipocyte fatty acid-binding protein (A-FABP)]by real-time PCR. The results showed as follows: 1 ) fat percentage of Wujin pigs was significantly increased with the increasing of dietary digestive energy level at the body weight of 60 and 100 kg ( P ＜ 0.01 ); 2 ) compared with those in group MDE, the expression levels of ACC, FAS and SREBP-lc of pigs in group HDE were significantly decreased at the body weight of 30 and 100 kg ( P ＜ 0.05 ), but significantly increased at the body weight of 60 kg ( P ＜ 0.05); 3 ) the expression level of A-FABP was increased significantly with the increasing of dietary digestive energy level at the body weight of 30 and 100 kg (P ＜ 0.05), but decreased significantly at the body weight of 60 kg ( P ＜ 0.05). The results indicate that high dietary energy level can significantly promote the expression of lipid anabolism related genes (ACC, FAS and SREBP-lc) but significantly inhibit the expression of fatty acid transport factor (A-FABP) and the transportation of free fatty acids. As a result, the de nove synthesis of free fatty acids is increased and the intake of exogenous fatty acids is decreased in the adipose tissue. [Chinese Journal of Animal Nutrition, 2011, 23(5) :781-788]
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