Publication de 4 numéros par an
ISSN Imprimer: 2155-014X
ISSN En ligne: 2155-0158
Increased Expression of Voltage-Dependent Anion Channel and Adenine Nucleotide Translocase and the Sensitivity of Ca2+-Induced Mitochondrial Permeability Transition Opening Pore in Old Rat Heart
RÉSUMÉ
We have investigated mRNA and protein expression of voltage-dependent anion channel (VDAC), mRNA adenine nucleotide translocase (ANT) as well as the sensitivity of the mitochondrial permeability transition pore (MPTP) to Ca2+ in the adult and the old rat heart. It was shown that in the old rats' hearts VDAC mRNA expression increased by 1.7 (P < 0.05) times and mRNA ANT expression increased 1.8 (P < 0.05) times in comparison with adult animals. Western Blot analysis has shown that the level of the VDAC protein expression in old rats' hearts also significantly increased as compared with adult animals. In old rats' hearts sensitivity of MPTP opening to calcium (10−7 − 10−4 M) determined by mitochondria swelling increased two-fold (P < 0.05). Therefore, an increased VDAC and ANT expression, as the main structure-functional components of the MPTP, and an increased sensitivity of MPTP opening to Ca2+ caused an increase in mitochondrial membranes' permeability in aging. Each of these factors may contribute to alterations in mitochondrial barrier properties and lead to mitochondrial dysfunction.