Wendel U, Langenbeck U
Biochem Med. 1984 Jun;31(3):294-302. doi: 10.1016/0006-2944(84)90085-1.
The interdependence of intra- and extracellular leucine and KICA concentration was studied in cultured MSUD and control fibroblasts. Intracellular KICA levels were measurable only after leucine load and were 1/20th to 1/40th that of leucine. In cells exposed to high KICA concentrations (2 mmole/liter) KICA accumulation followed linear kinetics, finally overwhelming the transamination capacity. Transamination of KICA to leucine became saturated at 2-6 mmole/liter of extracellular KICA. MSUD and control fibroblasts differed slightly in intracellular KICA concentrations, and only at high concentrations of leucine in medium. Release of KICA into the medium after leucine loading was found to be slightly increased in MSUD fibroblasts.
在培养的枫糖尿症（MSUD）和成纤维细胞对照中，研究了细胞内、外亮氨酸和α-酮异己酸（KICA）浓度的相互依赖性。仅在亮氨酸负荷后，细胞内KICA水平才可测量，其为亮氨酸水平的1/20至1/40。在暴露于高KICA浓度（2毫摩尔/升）的细胞中，KICA积累呈线性动力学，最终超过转氨能力。KICA向亮氨酸的转氨作用在细胞外KICA浓度为2 - 6毫摩尔/升时达到饱和。MSUD和成纤维细胞对照在细胞内KICA浓度上略有差异，且仅在培养基中亮氨酸浓度较高时如此。发现亮氨酸负荷后，MSUD成纤维细胞中KICA释放到培养基中的量略有增加。
