Mariash C N
Department of Medicine, University of Minnesota, Minneapolis 55455.
Endocrinology. 1989 Jan;124(1):212-7. doi: 10.1210/endo-124-1-212.
To determine whether the rapid response of hepatic mRNA-S14 to carbohydrate feeding was associated with an alteration in a specific hepatic nucleotide, acid extracts of liver tissue were analyzed by ion-paired reverse phase HPLC. A nucleotide present in nanomoles per g quantity correlated with the induction of this mRNA by sucrose. Four hours after sucrose feeding the content of this compound was 7 times greater than that in fasted rats. Furthermore, the response was rapid, attaining maximal levels 30 min after feeding, and remaining elevated for at least 4 h. The content of this nucleotide also correlated with the content of mRNA-S14 in the steady state, with the lowest levels of both mRNA-S14 and this nucleotide in fasted rats, intermediate levels in rats maintained on a regular chow diet, and the highest levels in rats fed a 60% sucrose diet for 4 days. Lastly, while the response of mRNA-S14 to thyroid hormone and sucrose is synergistic, the thyroidal state does not influence the response of this compound to sucrose. Thus, the interaction of thyroid hormone and sucrose on mRNA-S14 is distal to the generation of this compound. Based on the UV spectrum, HPLC retention, and [3H]adenosine labeling, this compound contains adenine. However, it is not any of the common adenine-containing mono- or oligonucleotides. These data indicate that a novel hepatic nucleotide is induced by sucrose and raise the possibility that this nucleotide is responsible for the induction of carbohydrate-responsive mRNAs.
为了确定肝脏mRNA-S14对碳水化合物喂养的快速反应是否与特定肝脏核苷酸的变化有关,通过离子对反相高效液相色谱法分析了肝组织的酸提取物。每克肝脏中以纳摩尔量存在的一种核苷酸与蔗糖诱导该mRNA相关。蔗糖喂养4小时后,这种化合物的含量比禁食大鼠高7倍。此外,反应迅速,喂食后30分钟达到最高水平,并至少持续升高4小时。这种核苷酸的含量也与稳态下mRNA-S14的含量相关,禁食大鼠中mRNA-S14和这种核苷酸的水平最低,正常饮食的大鼠中为中等水平,而喂食60%蔗糖饮食4天的大鼠中水平最高。最后,虽然mRNA-S14对甲状腺激素和蔗糖的反应具有协同作用,但甲状腺状态并不影响这种化合物对蔗糖的反应。因此,甲状腺激素和蔗糖对mRNA-S14的相互作用发生在该化合物产生之后。根据紫外光谱、高效液相色谱保留时间和[3H]腺苷标记,这种化合物含有腺嘌呤。然而,它不是任何常见的含腺嘌呤单核苷酸或寡核苷酸。这些数据表明一种新型肝脏核苷酸由蔗糖诱导产生,并增加了这种核苷酸负责诱导碳水化合物反应性mRNA的可能性。