Menadione-induced apoptosis: roles of cytosolic Ca(2+) elevations and the mitochondrial permeability transition pore.

Gerasimenko, Julia V, Gerasimenko, Oleg V, Palejwala, Altaf, Tepikin, Alexei V, Petersen, Ole H and Watson, Alastair J M (2002) Menadione-induced apoptosis: roles of cytosolic Ca(2+) elevations and the mitochondrial permeability transition pore. Journal of Cell Science, 115 (Pt 3). pp. 485-497. ISSN 0021-9533

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Abstract

In normal pancreatic acinar cells, the oxidant menadione evokes repetitive cytosolic Ca(2+) spikes, partial mitochondrial depolarisation, cytochrome c release and apoptosis. The physiological agonists acetylcholine and cholecystokinin also evoke cytosolic Ca(2+) spikes but do not depolarise mitochondria and fail to induce apoptosis. Ca(2+) spikes induced by low agonist concentrations are confined to the apical secretory pole of the cell by the buffering action of perigranular mitochondria. Menadione prevents mitochondrial Ca(2+) uptake, which permits rapid spread of Ca(2+) throughout the cell. Menadione-induced mitochondrial depolarisation is due to induction of the permeability transition pore. Blockade of the permeability transition pore with bongkrekic acid prevents activation of caspase 9 and 3. In contrast, the combination of antimycin A and acetylcholine does not cause apoptosis but elicits a global cytosolic Ca(2+) rise and mitochondrial depolarisation without induction of the permeability transition pore. Increasing the cytosolic Ca(2+) buffering power by BAPTA prevents cytosolic Ca(2+) spiking, blocks the menadione-elicited mitochondrial depolarisation and blocks menadione-induced apoptosis. These results suggest a twin-track model in which both intracellular release of Ca(2+) and induction of the permeability transition pore are required for initiation of apoptosis.

Item Type: Article
Faculty \ School: Faculty of Medicine and Health Sciences > Norwich Medical School
Depositing User: Rhiannon Harvey
Date Deposited: 14 Jul 2011 09:02
Last Modified: 21 Apr 2020 20:41
URI: https://ueaeprints.uea.ac.uk/id/eprint/33695
DOI:

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