Melvin M A, Melvin W T, Keir H M
Cancer Res. 1978 Sep;38(9):3055-8.
The growth of BHK-21/C13 cells in monolayer cultures was inhibited by 6-thioguanosine. Accumulation of putrescine, spermidine, and spermine was inhibited by 6-thioguanosine, and cells incubated in the presence of the drug had a decreased content of polyamines relative to control cells. These effects were more marked for spermidine than for spermine or putrescine. Consequently, the intracellular spermidine:spermine molar ratio was decreased in cells exposed to the drug. Cells, the polyamines of which had been labeled with [3H]putrescine, were incubated in the presence or absence of 6-thioguanosine. More polyamines were lost from cells exposed to the drug than from control cells. The radioactive material excreted was predominantly spermidine, both as its free form and in a conjugated form, even when the cells contained large amounts of labeled spermine. This release of spermidine from BHK-21/C13 cells into the culture medium was a specific response of the cells to alterations in growth potential rather than a consequence of leakage due to cell lysis.
6-硫代鸟苷可抑制单层培养的BHK-21/C13细胞的生长。6-硫代鸟苷可抑制腐胺、亚精胺和精胺的积累，与对照细胞相比，在药物存在下培养的细胞中多胺含量降低。这些作用对亚精胺的影响比对精胺或腐胺更为显著。因此，暴露于该药物的细胞内亚精胺：精胺摩尔比降低。用[3H]腐胺标记多胺的细胞，在有或无6-硫代鸟苷的情况下进行培养。与对照细胞相比，暴露于药物的细胞中损失的多胺更多。即使细胞含有大量标记的精胺，排泄出的放射性物质主要也是亚精胺，包括其游离形式和结合形式。BHK-21/C13细胞中亚精胺释放到培养基中是细胞对生长潜能改变的一种特异性反应，而不是细胞裂解导致泄漏的结果。
