PERMEATION OF DIBUTYRYL CAMP INTO HELA-CELLS AND ITS CONVERSION TO MONOBUTYRYL CAMP
PERMEATION OF DIBUTYRYL CAMP INTO HELA-CELLS AND ITS CONVERSION TO MONOBUTYRYL CAMP
复制标题
DOI：
10.1016/s0006-291x(72)80242-0
复制
发表时间：
1972-01-01
影响因子：
3.1
通讯作者：
HILZ, H
中科院分区：
文献类型：
--
作者：
KAUKEL, E;HILZ, H
当暴露于 HeLa 培养物时，3H-二丁酰 cAMP (DBcAMP) 被证明对细胞外降解具有相当的抵抗力。它被细胞吸收并导致单丁酰 cAMP (MBcAMP) 的积累，与 DBcAMP 相比，MBcAMP 显示出与 Gilman 的 (1) cAMP 结合蛋白的高亲和力。在这些条件下，cAMP和DBcAMP在细胞中的积累程度不高。除DBcAMP外，cAMP在细胞外快速降解为各种代谢物，包括被细胞吸收并转化为嘌呤核苷酸的腺苷。只有在细胞外浓度较高的情况下，cAMP 才能渗透到细胞中并导致细胞内 cAMP 水平短暂升高。然而，当向培养物中添加相似浓度的 DBcAMP 时，这些水平从未达到稳定增加的蛋白激酶结合物质 (MBcAMP + cAMP) 的浓度。这些结果表明，DBcAMP 的持续激素样作用主要是通过对细胞外和细胞内磷酸二酯酶的高抵抗性以及通过酶转化为细胞中积累的 MBcAMP 来实现的。
3H-Dibutyryl cAMP (DBcAMP) when exposed to HeLa cultures proved rather resistant toextracellulardegradation. It was taken up by the cells and led to an accumulation of monobutyryl cAMP (MBcAMP), which — in contrast to DBcAMP — showed a high affinity to Gilman's (1) cAMP-binding protein. cAMP and DBcAMP were not accumulated in the cells to a comparable degree under these conditions.Other than DBcAMP, cAMP was rapidly degraded extracellulary to various metabolites including adenosine which was taken up by the cells and converted to purine nucleotides. Only at high extracellular concentrations cAMP could permeate the cells and lead to a transient rise in intracellular cAMP levels. These levels, however, never reached the steadily increasing concentrations of protein kinase-binding substances (MBcAMP + cAMP) when similar concentrations of DBcAMP were added to cultures.These results indicate that the sustained hormone-like actions of DBcAMP come about mainly by a high resistance to extracellular and intracellular phosphodiesterase as well as by the enzymic conversion to MBcAMP accumulating in the cells.