Quillard M, Husson A, Lavoinne A
Groupe de Biochimie et de Physiopathologie Digestive et Nutritionnelle, Faculté Médecine-Pharmacie de Rouen, France.
Eur J Biochem. 1996 Feb 15;236(1):56-9. doi: 10.1111/j.1432-1033.1996.00056.x.
Glutamine, one of the most efficient substrates in the urea cycle, was found to induce the accumulation of argininosuccinate synthetase (ASS) mRNA in primary cultured rat hepatocytes. The inducing action of glutamine was obtained at various stages of development and a half-maximal effect was observed at about 3 mM glutamine. This effect was apparent from 6 h and persisted for at least 48 h. NH4Cl addition up to 5 mM did not significantly change the ASS mRNA level. Like glutamine, hypoosmotic medium and aminoisobutyric acid (conditions known to increase cell volume) also increased the ASS mRNA level, which was, in contrast, decreased by hyperosmotic medium. These results demonstrate that the glutamine-induced swelling may participate in the observed increase of the ASS mRNA level. This increase in the ASS mRNA level was associated with an increase in ASS activity.
谷氨酰胺是尿素循环中最有效的底物之一，研究发现它能诱导原代培养的大鼠肝细胞中精氨琥珀酸合成酶（ASS）mRNA的积累。在发育的各个阶段都能观察到谷氨酰胺的诱导作用，在约3 mM谷氨酰胺时可观察到半数最大效应。这种效应在6小时时明显，并持续至少48小时。添加高达5 mM的NH4Cl不会显著改变ASS mRNA水平。与谷氨酰胺一样，低渗培养基和氨基异丁酸（已知可增加细胞体积的条件）也会增加ASS mRNA水平，相反，高渗培养基则会降低该水平。这些结果表明，谷氨酰胺诱导的细胞肿胀可能参与了观察到的ASS mRNA水平的升高。ASS mRNA水平的这种升高与ASS活性的增加相关。
