神经内分泌因子对体外培养新生犊牛肝细胞MTP mRNA表达的影响

为了阐明神经内分泌因子在奶牛肝脂蛋白组装与转运过程中的调控作用,通过向体外培养的新生犊牛肝细胞添加胰岛素、胰高血糖素和瘦蛋白,采用内对照RT-PCR方法检测神经内分泌因子对体外培养新生犊牛肝细胞微粒体甘油三酯转运蛋白(MTP)mRNA丰度的影响。结果显示,随着细胞培养液中胰岛素和胰高血糖素浓度升高,MTP mRNA的丰度呈现剂量依赖性下降(P<0.01);随着瘦蛋白浓度的增加,MTP mRNA的丰度先升高后降低(P<0.01或P<0.05)。这表明胰岛素和胰高血糖素对肝细胞MTP mRNA表达具有抑制作用,呈现剂量依赖性;瘦蛋白对肝细胞MTP mRNA表达具有低剂量促进而高剂量抑制的双重作用,且均呈现剂量依赖性。

Effect of neuroendocrine factors on expression of MTP mRNA in newborn calf hepatocytes in vitro

The present trail was conducted to light the regulating effect of neuroendocrine factors on assembly and secretion of lipoprotein in liver of dairy cows.Different concentrations of insulin,glucagons and leptin were added into monolayer culture media of primary-cultured newborn calf hepatocytes respectively.After 24 hours,abundance of MTP mRNA in primary-cultured newborn calf hepatocytes was detected by semiquantitative RT-PCR.The result showed that with increasing concentrations of insulin and glucagons,abundance of MTP mRNA in hepatocytes was down-regulated significantly with dose-dependence (P<0.01).However,with increasing concentrations of leptin,abundance of MTP mRNA in hepatocytes was up-regulated,and then decreased(P<0.01 or P<0.05).It was concluded that neuroendocrine factors such as insulin,glucagons and leptin could regulated expression of MTP mRNA.