Gitomer W L, Veech R L
Toxicol Ind Health. 1986 Sep;2(3):299-307. doi: 10.1177/074823378600200308.
Hepatocytes that were isolated from 48 hr starved rats and incubated in Krebs-Henseleit bicarbonate buffer containing 10 microM A23187, 10mM l-lactate, 1mM pyruvate and 2mM l-lysine were found to contain 0.064 mumol of inorganic pyrophosphate/g wet wgt cells. Addition of either 20mM acetate or butyrate, which caused the formation of pyrophosphate in both the cytosol and the mitochondrial matrix or only the matrix, resulted in an increase of 0.915 and 1.91 mumol pyrophosphate/g wet wgt cells, respectively. The accumulation of pyrophosphate was shown to be non-linear with time and dependent on the calcium concentration of the incubation media. In contrast, incubations containing a combination of 10 mM NH4Cl and 5 mM ornithine, which resulted in the formation of pyrophosphate only in the cytosol, had a pyrophosphate content of 0.032 mumol/g wgt cells. When isolated hepatocytes that had been incubated with acetate or butyrate were subjected to digitonin fractionation, all of the recoverable pyrophosphate was present in the particulate fraction. It is concluded that pyrophosphate accumulates in isolated rat hepatocytes only in the presence of calcium and a calcium ionophore, only within the mitochondrial matrix and only when pyrophosphate is formed within the mitochondrial matrix.
从饥饿48小时的大鼠中分离出的肝细胞，在含有10微摩尔A23187、10毫摩尔L-乳酸、1毫摩尔丙酮酸和2毫摩尔L-赖氨酸的Krebs-Henseleit碳酸氢盐缓冲液中孵育后，发现每克湿重细胞含有0.064微摩尔无机焦磷酸。添加20毫摩尔乙酸盐或丁酸盐，会导致胞质溶胶和线粒体基质或仅线粒体基质中形成焦磷酸，结果每克湿重细胞中焦磷酸分别增加0.915和1.91微摩尔。焦磷酸的积累显示出与时间呈非线性关系，且依赖于孵育培养基中的钙浓度。相比之下，含有10毫摩尔氯化铵和5毫摩尔鸟氨酸的孵育液，只会导致胞质溶胶中形成焦磷酸，其焦磷酸含量为每克湿重细胞0.032微摩尔。当用乙酸盐或丁酸盐孵育过的分离肝细胞进行洋地黄皂苷分级分离时，所有可回收的焦磷酸都存在于颗粒部分。得出的结论是，焦磷酸仅在有钙和钙离子载体存在时，仅在线粒体基质内，且仅当焦磷酸在线粒体基质内形成时，才会在分离的大鼠肝细胞中积累。
