Stein W D, Klein A
Biochim Biophys Acta. 1983 Feb 16;762(1):94-101. doi: 10.1016/0167-4889(83)90121-0.
Uridine uptake by mouse or hamster cells grown in conditions which support good growth is very sensitive to inhibition by cyanide and azide, at concentrations which only slightly reduce overall cellular ATP levels. Iodoacetate, when present alone, reduces uridine uptake only insofar as it reduces cellular ATP levels. At concentrations which by themselves do not affect uridine uptake, iodoacetate greatly reduces the sensitivity of uridine uptake to cyanide or azide. The effect of cyanide is on intracellular trapping of uridine and not on its transport into the cell. The specific effect of cyanide is confined to uridine and not found for the uptake of adenine, thymidine or 2-deoxyglucose. The effect is of rapid onset (within 2 min) and is rapidly reversible (also within 2 min). Phosphorylation of uridine in homogenised cells or in Triton X-100-permeabilised cells is unaffected by cyanide. The data are interpreted in terms of a model in which intracellular trapping of uridine is subject to multiple controls, including one regulated by some factor requiring intact functioning of the mitochondrion. These multiple control systems interact synergistically to affect trapping of uridine by the intact cell.
在有利于良好生长的条件下培养的小鼠或仓鼠细胞摄取尿苷，对氰化物和叠氮化物的抑制非常敏感，而这些抑制剂的浓度只会略微降低细胞总体ATP水平。单独存在时，碘乙酸仅在降低细胞ATP水平的程度上降低尿苷摄取。在自身浓度不影响尿苷摄取的情况下，碘乙酸会大大降低尿苷摄取对氰化物或叠氮化物的敏感性。氰化物的作用在于细胞内尿苷的捕获，而非其进入细胞的转运过程。氰化物的特定作用仅限于尿苷，在腺嘌呤、胸苷或2-脱氧葡萄糖的摄取中未发现此现象。该作用起效迅速（2分钟内），且迅速可逆（同样在2分钟内）。在匀浆细胞或经曲拉通X-100通透处理的细胞中，尿苷的磷酸化不受氰化物影响。这些数据依据一个模型进行解释，在该模型中，尿苷的细胞内捕获受到多种控制，包括一种受某种需要线粒体完整功能的因子调控的控制。这些多种控制系统协同相互作用，以影响完整细胞对尿苷的捕获。
