title: Excretion of spermidine from BHK-21/C13 cells exposed to 6-thioguanosine.
abstract: 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.
mesh_terms: D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D006151:Guanosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D011700:Putrescine / Q000378:metabolism; D013095:Spermidine / Q000378:metabolism*; D013096:Spermine / Q000378:metabolism; D013872:Thionucleosides / Q000494:pharmacology*
chemical_list: D013872:Thionucleosides; D006151:Guanosine; D013096:Spermine; C005783:6-thioguanosine; D013095:Spermidine; D011700:Putrescine