par Valverde, Isabel;Malaisse, Willy 
Référence IRCS Medical Science, 8, page (191)
Publication Publié, 1980
Référence IRCS Medical Science, 8, page (191)
Publication Publié, 1980
Article révisé par les pairs
| Résumé : | It was recently proposed that the redox state may be a major determinant of calcium transport across biological membranes. Reduced pyridine nucleotides and/or reduced glutathione may affect disulphide bridges in membrane-associated proteins acting as calcium channels or affect calcium transport by interfering with the functional behavior of native ionophoretic systems acting as a calcium carriers. The latter possibility was tested in the present study. In the presence of X537A and absence of both GSH and GSSG the amount of calcium translocated differed greatly as a function of the pH and calcium concentration of the aqueous phase. Under all experimental conditions, GSSG (3.75 mM) markedly inhibited calcium translocation. By contrast, GSH generally failed to affect significantly calcium translocation. When GSH and GSSG were used in equimolar amounts to give the same total concentration (3.75 mM) as that used when each compound was tested alone, the amount of calcium translocated, relative to the control value (no glutathione), yielded a value (88.7±2.3%) in between that found with GSH alone (98.9±1.3%) and GSSG alone (80.7±5.3%). |
