introduction: previous studies have indicated a relationship between mptp pore and av nodal rate-dependent properties. the aim of present study was to determine acute direct effects of cyclosporine on extracellular field potential of isolated rabbit av node during experimental atrial fibrillation. methods: in one group of male new zealand rabbits (1.5-2.5 kg) cumulative concentrations of cyclos...

Mitochondrial permeability transition pores represent a multiprotein complex that includes components of both inner and outer membrane. The pores regulate transport of ions and peptides in and out of mitochondria, and their regulation is associated with a general mechanism for maintaining Ca(2+) homeostasis in the cell and apoptosis. Various pathologic factors may induce a pathologic activation...

Mitochondrial dysfunction occurs early in the progression of Alzheimer's disease. Amyloid-β peptide has deleterious effects on mitochondrial function and contributes to energy failure, respiratory chain impairment, neuronal apoptosis, and generation of reactive oxygen species in Alzheimer's disease. The mechanisms underlying amyloid-β induced mitochondrial stress remain unclear. Emerging eviden...

This study aims to evaluate the cytotoxicity of resveratrol on QGY-7701 cells via a cell viability assay, and determine the cytological alterations and damages that result. Resveratrol was found to inhibit QGY-7701 cell growth and decrease their viability in a remarkably dose-dependent manner. Resveratrol exposure also induced an increase in Caspase-3 activity and a decrease in Bcl-2, which cau...

A critical event in ischemia-based cell death is the opening of the mitochondrial permeability transition pore (MPTP). However, the molecular identity of the components of the MPTP remains unknown. Here, we determined that the Bcl-2 family members Bax and Bak, which are central regulators of apoptotic cell death, are also required for mitochondrial pore-dependent necrotic cell death by facilita...

Cytochrome c release and the mitochondrial permeability transition (PT), including loss of the transmembrane potential (Deltapsi), play an important role in apoptosis. Using isolated mitochondria, we found that recombinant Bax and Bak, proapoptotic members of the Bcl-2 family, induced mitochondrial Deltapsi loss, swelling, and cytochrome c release. All of these changes were dependent on Ca2+ an...

Nanosecond, high-voltage electric pulses (nsEP) induce permeabilization of the plasma membrane and the membranes of cell organelles, leading to various responses in cells including cytochrome c release from mitochondria and caspase activation associated with apoptosis. We report here evidence for nsEP-induced permeabilization of mitochondrial membranes in living cells. Using three different met...

Mitochondria increase their outer and inner membrane permeability to solutes, protons and metabolites in response to a variety of extrinsic and intrinsic signaling events. The maintenance of cellular and intraorganelle ionic homeostasis, particularly for Ca2+, can determine cell survival or death. Mitochondrial death decision is centered on two processes: inner membrane permeabilization, such a...

We found that both benzyl isothiocyanate (ITC) and phenyl ITC inhibited respiration in the mitochondria in an electrophilic reaction-dependent manner. ITC-induced mitochondrial swelling and cytochrome c release were prevented by cyclosporin A, indicating that they are mediated through the ITC moiety-dependent reaction to critical thiol groups for the opening of membrane permeability transition-...

Biological organisms depend on a variety of mechanisms to remove defective components. Such was originally thought to be the function of the mitochondrial permeability transition, in which high-conductance permeability transition pores (PTP) form in the inner mitochondrial membrane, causing immediate matrix depolarization, Ca release, reversal of ATP synthase, matrix swelling, and eventually ru...