Acta Med. 2009, 52: 69-72
Tissue Specific Sensitivity of Mitochondrial Permeability Transition Pore to Ca2+ Ions
Ca2+-induced opening of the mitochondrial permeability transition pore (MPTP) is involved in induction of apoptotic and necrotic processes. We studied sensitivity of MPTP to calcium using the model of Ca2+-induced, cyclosporine A-sensitive mitochondrial swelling. Presented data indicate that the extent of mitochondrial swelling (dA520/4 min) induced by addition of 25 μM Ca2+ is seven-fold higher in liver than in heart mitochondria (0.564 ± 0.08/0.077± 0.01). The extent of swelling induced by 100 μM Ca2+ was in liver tree times higher than in heart mitochondria (0.508±0.05/ 0.173±0.02). Cyclosporine A sensitivity showed that opening of the MPTP is involved. We may thus conclude that especially at low Ca2+ concentration heart mitochondria are more resistant to damaging effect of Ca2+ than liver mitochondria. These finding thus support hypothesis that there exist tissue specific strategies of cell protection against induction of the apoptotic and necrotic processes.
Keywords
Mitochondria, MPTP, Swelling, Cell death, Apoptosis, Necrosis.
Funding
This work was supported by the Ministry of Education Research Project MSM VZ 0021620820 and Institutional project AVOZ 501509.
References
Copyright
Published by the Karolinum Press. For permission to use please write to actamedica@lfhk.cuni.cz.
