为了研究体外胰岛素对猪脂肪组织脂肪代谢及相关基因表达的影响,对取自于7日龄大白×长白杂种仔猪皮下脂肪组织的脂肪细胞,经原代培养,用0～400nmol/L胰岛素处理48h,采用油红O染色提取、甘油试剂盒和半微量RT-PCR分别测定了脂肪细胞生脂和脂解的累计变化,以及转录因子固醇调控元件结合蛋白(SREBP)-1c和碳水化合物反应元件结合蛋白(ChREBP)、脂肪酸合成酶(FAS)、乙酰辅酶A羧化酶(ACC1)和激素敏感脂酶(HSL)基因mRNA水平的变化.结果表明,低糖条件下(5 mmol/L)下,胰岛素不影响原代培养猪脂肪细胞ChREBP和ACC1转录表达;胰岛素(200 nmol/L例外)明显促进FAS转录表达,100～300 nmol/L也显著增强SREBP-1c表达.但二者表达变化不一致,在原代猪脂肪细胞胰岛素是否是通过SREBP-1c途径调控FAS转录尚待进一步研究;高浓度胰岛素(300～400 nmol/L)显著促进脂肪细胞HSL表达和脂解活性.%Primary adipocytes from subcutaneous adipose tissue samples obtained from 7 day-old Yorkshire ×Landrace crossbreed piglets were exposed to 0～400 nmol/L of insulin for 48 h. The accumulated triglyceride was measured through Oil Red O staining and the cumulative glycerol released was determined to assess lipolytic activity in adipocytes. The variance was assessed in transcripton level of sterol regulatory element binding protein (SREBP)-1c, carbohydrate response element binding protein (ChREBP),acetyl-CoA carboxylase α (ACC1), fatty acid synthase (FAS), and hormone sensitive lipase (HSL) using RT-PCR. The results showed that ChREBP and ACC1 mRNA levels were not influenced alone by insulin under low glucose (5 nmol/L). FAS mRNA level was markedly stimulated by all other doses except 200 nmol/L insulin and SREBP-1c mRNA level increased with 100～300 nmol/L insulin. High insulin doses (300 and 400 nmol/L) increased the HSL mRNA level as well as the lipolytic activity.
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