Asselineau D, Bell E
Mech Ageing Dev. 1984 Apr-May;25(1-2):257-66. doi: 10.1016/0047-6374(84)90146-5.
The stimulation of prolylhydroxylase activity by ascorbate in IMR 90 fibroblasts grown as monolayer decreases with increasing population doubling level, but the enzyme is not stimulated in IMR 90 fibroblasts of either low or high population doubling level incorporated into collagen lattices in which they cease to divide. The capacity to be activated is restored when cells are released from the lattice. We consider that reduction of stimulation of prolylhydroxylase activity by ascorbate as the population doubling level of cells grown as monolayer increases is not a phenomenon of cell aging. Rather, it is due to an increase in the size of the noncycling subpopulation whose state of differentiation is not the same as that of cells in cycle.
在单层培养的IMR 90成纤维细胞中，随着群体倍增水平的增加，抗坏血酸对脯氨酰羟化酶活性的刺激作用减弱，但在掺入胶原晶格且不再分裂的低或高群体倍增水平的IMR 90成纤维细胞中，该酶未受到刺激。当细胞从晶格中释放出来时，被激活的能力得以恢复。我们认为，随着单层培养细胞的群体倍增水平增加，抗坏血酸对脯氨酰羟化酶活性的刺激作用减弱并非细胞衰老现象。相反，这是由于非循环亚群大小增加，其分化状态与处于周期中的细胞不同。
