| Autor: |
D A, Kuznetsov, S E, Arkhantel'skiĭ, A G, Berdieva, A A, Markarian, P Z, Khasigov, T M, Gatagonova, S A, Ktsova, M A, Orlova |
| Rok vydání: |
2005 |
| Předmět: |
|
| Zdroj: |
Biofizika. 50(1) |
| ISSN: |
0006-3029 |
| Popis: |
The ATP-generating activity of rat myocardial mitochondria and intramitochondrial creatine kinase was examined as a function of the isotopy of the incubation medium magnesium pool. The study was performed using in vitro systems prepared from the hearts of animals injected with 1-methylnicotine amide, which suppresses the NAD (NADP)-dependent reactions in vivo. It was shown that the presence of the 25Mg paramagnetic cations essential by compensates for the intramitochondrial ATP deficiency caused by the 1-methyl-nicotine amide-induced blockade of oxidative phosphorylation. This effect is hardey achievable in systems where the magnesium pool consists of isotopes with a zero nuclear spin (24Mg, 26Mg). The restoration of mitochondrial ATP synthesis involves the participation of creatine kinase since the activity of the latter does not depend on 1-methyl-nicotine amide. In this case, the high efficiency of this restaration seems to be a spin-selective phenomenon which requires predominantly 25Mg2+ cations. A possible meaning of the data for further studies on the mechanisms of enzymatic catalysis regulation is discussed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
