| Autor: |
Shinlova OP, Kosterin SA, Veklich TA |
| Jazyk: |
ruština |
| Zdroj: |
Biokhimiia (Moscow, Russia) [Biokhimiia] 1996 Aug; Vol. 61 (8), pp. 1440-7. |
| Abstrakt: |
The effects of ruthenium red, pH, and sodium ions on active and passive Ca2+ transport were studied in digitonin-treated (0.1 mg/ml) suspension of myometrial cells using radiolabeled 45Ca2+. The inhibitor of mitochondrial Ca2+ accumulation ruthenium red (10 microM) suppressed active accumulation of the cation in permeabilized myocytes by 78-85%. Ruthenium red-sensitive Ca2+ accumulation significantly (10-fold, mean) exceeds ruthenium red-resistant Mg2+, ATP-dependent Ca2+ accumulation assayed in the absence of oxalate and inhibited by 50 nM tapsigargin (blocker of endo/sarcoplasmic reticulum calcium pump). Acidification of incubation medium (pH 8.0-6.0, Tris-malcate/KOH buffer) inhibits ruthenium red-sensitive active Ca2+ accumulation in permeabilized myocytes and passive release of this cation in the dilution medium after blockage of mitochondrial Ca2+ accumulation by ruthenium red. Partial isotonic substitution of KCl (135-95 mM) with NaCl (15-55 mM) in incubation medium did not affect the initial rate of active ruthenium red-sensitive Ca2+ accumulation and the kinetics of passive Ca2+ release from permeabilized cells after blockade of active Ca2+ accumulation by ruthenium red. Mechanism of Ca2+ exchange in myometrial mitochondria is discussed. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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