Leclercq B, Hermier D, Guy G
INRA, Station de Recherches Avicoles, Nouzilly, France.
Reprod Nutr Dev. 1990;30(6):701-15. doi: 10.1051/rnd:19900607.
Metabolism of very low density lipoproteins (VLDL) has been compared in fat (FL) and lean (LL) lines of chicken. When refed after fasting, plasma triglyceride concentration reached a significantly higher plateau in FL, although their feed consumption was lower than in LL. Newly synthesized VLDL were studied using anti-lipoprotein lipase antibodies. VLDL triglyceride (TG) concentrations were increased by antibody injection and reached a higher concentration in FL plasma than in LL. Newly synthesized VLDL exhibited a similar lipid composition. Fatty acid profiles were also similar when birds ingested a very low fat diet. Comparison of in vitro affinity of lipoprotein lipase and VLDL from both genotypes did not reveal any difference in Km and Vmax. [14C]labelled VLDL from fat or lean donors were prepared and were injected into chickens from both genotypes. Fractional rate constants did not differ between lines. However, as plasma VLDL-TG pools were very different, plasma turnover was higher in FL than in LL. About 3-fold more VLDL-TG were incorporated in abdominal fat of FL than in LL. Difference in fattening between both genotypes seem to be due to both increased VLDL secretion and VLDL removal from plasma without difference in VLDL characteristics.
已对鸡的脂肪系（FL）和瘦肉系（LL）中极低密度脂蛋白（VLDL）的代谢进行了比较。禁食后再喂食时，FL系鸡血浆甘油三酯浓度达到的稳定水平显著高于LL系，尽管其采食量低于LL系。使用抗脂蛋白脂肪酶抗体对新合成的VLDL进行了研究。抗体注射使VLDL甘油三酯（TG）浓度升高，且FL系血浆中的浓度高于LL系。新合成的VLDL表现出相似的脂质组成。当鸡摄入极低脂肪饮食时，脂肪酸谱也相似。对两种基因型的脂蛋白脂肪酶和VLDL的体外亲和力进行比较，未发现Km和Vmax有任何差异。制备了来自脂肪系或瘦肉系供体的[14C]标记VLDL，并将其注射到两种基因型的鸡体内。品系间的分数速率常数没有差异。然而，由于血浆VLDL-TG池差异很大，FL系的血浆周转率高于LL系。FL系腹部脂肪中掺入的VLDL-TG比LL系多约3倍。两种基因型育肥的差异似乎是由于VLDL分泌增加以及VLDL从血浆中清除，而VLDL特性没有差异。
