Pietu G, Munsch N, Mousset S, Frayssinet C
Cell Tissue Kinet. 1979 Mar;12(2):153-60. doi: 10.1111/j.1365-2184.1979.tb00122.x.
We partially purified an inhibitory factor (LIFE), isolated from 105,000 g supernatant of a saline adult rat liver homogenate. LIF stopped in vitro cell multiplication by blocking the G1--S transition, and reduced in vivo [3H]thymidine incorporation into liver DNA in two-thirds hepatectomized rats. This reduction in DNA synthesis was observed at 24 hr after hepatectomy, even when the LIF was injected before the beginning of the S phase, 10 hr after hepatectomy, i.e. when DNA polymerase activity had not yet increased. Under these experimental conditions, LIF in vivo treatment prevented alpha DNA polymerase activity from increasing after partial hepatectomy, so that enzyme activity at 24 hr in LIF-treated rats decreased compared to the controls. No direct inhibitory effect of LIF on alpha DNA polymerase was detected. LIF did not affect beta DNA polymerase. These results suggest that LIF plays a part in controlling liver growth.
我们从成年大鼠肝脏生理盐水匀浆的105,000 g上清液中部分纯化了一种抑制因子（LIFE）。LIF通过阻断G1-S期转换来抑制体外细胞增殖，并减少了三分之二肝切除大鼠体内[3H]胸苷掺入肝脏DNA的量。即使在肝切除10小时后（即DNA聚合酶活性尚未增加时），在S期开始前注射LIF，在肝切除24小时后仍观察到DNA合成减少。在这些实验条件下，LIF体内治疗可防止部分肝切除后α-DNA聚合酶活性增加，因此与对照组相比，LIF处理大鼠在24小时时的酶活性降低。未检测到LIF对α-DNA聚合酶的直接抑制作用。LIF不影响β-DNA聚合酶。这些结果表明，LIF在控制肝脏生长中起作用。
