| Autor: |
Mamont, Pierre S., Joder-Ohlenbusch, Anne-Marie, Siat, Marlyse |
| Předmět: |
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| Zdroj: |
European Journal of Biochemistry; 7/1/83, Vol. 133 Issue 3, p613-616, 4p |
| Abstrakt: |
Recent evidence has indicated a role for the acetyl derivatives of polyamines, particularly N8-mono-acetylspermidine, as activators of L-ornithine decarboxylase in rat hepatoma tissue culture (HTC) cells. This is in contrast with the well-described negative regulatory control of ornithine decarboxylase exerted by their non-acetylated counterparts. Because of the possibility of a rapid extracellular and intracellular catabolism of the acetyl derivatives of polyamines, the methabolism of N8-monoacetylspermidine and its effect on HTC cell ornithine decarboxylase have been investigated, under conditions which climinate its extracellular catabolism. Differing from previous reports, we demonstrate that N8-monoacetylspermidine does not elevate ornithine decarboxylae activity when added at low concentrations to the culture medium of HTC cells. Higher concentrations decrease ornithine decarboxylase activity in a dose-dependent manner. This effect cannot be unambiguously attributed to the effect of the acetyl derivative itself, because of the presence in situ of a very active N8-monoacetylspermidine deacetylase, which generates spermidine intracellularly. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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