scholarly journals Reply to Rutter et al.: The roles of cytosolic and intramitochondrial Ca2+ and the mitochondrial Ca2+-uniporter (MCU) in the stimulation of mammalian oxidative phosphorylation

2020 ◽  
Vol 295 (30) ◽  
pp. 10507-10507
Author(s):  
Frank N. Gellerich ◽  
Marten Szibor ◽  
Zemfira Gizatullina ◽  
Volkmar Lessmann ◽  
Michael Schwarzer ◽  
...  
Keyword(s):  
Oxidative Phosphorylation ◽  
Stimulation Of

scholarly journals Training-induced adaptation of oxidative phosphorylation in skeletal muscles

2003 ◽  
Vol 374 (1) ◽  
pp. 37-40 ◽  
Author(s):  
Bernard KORZENIEWSKI ◽  
Jerzy A. ZOLADZ
Keyword(s):  
Quantitative Analysis ◽  
Oxidative Phosphorylation ◽  
Skeletal Muscles ◽  
Oxygen Uptake Kinetics ◽  
Mitochondrial Proteins ◽  
Muscle Training ◽  
Direct Stimulation ◽  
Atp Supply ◽  
Parallel Activation ◽  
Stimulation Of

Muscle training/conditioning improves the adaptation of oxidative phosphorylation in skeletal muscles to physical exercise. However, the mechanisms underlying this adaptation are still not understood fully. By quantitative analysis of the existing experimental results, we show that training-induced acceleration of oxygen-uptake kinetics at the onset of exercise and improvement of ATP/ADP stability due to physical training are mainly caused by an increase in the amount of mitochondrial proteins and by an intensification of the parallel activation of ATP usage and ATP supply (increase in direct stimulation of oxidative phosphorylation complexes accompanying stimulation of ATP consumption) during exercise.

A magnesium-responsive defect of respiration and oxidative phosphorylation in skeletal muscle mitochondria of dystrophic hamsters

1970 ◽  
Vol 48 (12) ◽  
pp. 1332-1338 ◽  
Author(s):  
K. Wrogemann ◽  
M. C. Blanchaer ◽  
B. E. Jacobson
Keyword(s):  
Skeletal Muscle ◽  
Oxidative Phosphorylation ◽  
Respiratory Rate ◽  
Test System ◽  
Muscle Mitochondria ◽  
Skeletal Muscle Mitochondria ◽  
Muscle Necrosis ◽  
Presence And Absence ◽  
Stimulation Of

Skeletal muscle mitochondria were isolated in the presence and absence of the proteinase Nagarse from dystrophic hamsters of the BIO 14.6 strain, aged 45–196 days, and from normal hamsters. Mitochondria from the dystrophic animals prepared by glass-on-glass homogenization without Nagarse in 0.25 M sucrose – 1 mM EDTA, pH 7.4, did not differ from normal in their respiratory rate or capacity for oxidative phosphorylation. However, these functions were subnormal in mitochondria isolated with Nagarse from the same animals, both in the presence and absence of albumin. Respiration measured with an O2 electrode was reduced by 50–70% and the stimulation of O2 uptake normally seen after ADP addition was minimal or absent. This was most marked in mitochondria from young hamsters about 65 days old with muscle necrosis. The defect was ameliorated by addition to the Polarographie test system of an ATP trap or of Mg2+, one of the trap constituents. This ion, when added to the defective mitochondria prior to ADP and substrate, restored respiration and oxidative phosphorylation to values that did not differ significantly from those found with skeletal muscle mitochondria of normal hamsters.

STUDIES ON THE INHIBITION OF THE MITOCHONDRIAL ATP-ase BY REDUCTION OF THE RESPIRATORY CHAIN

1960 ◽  
Vol 38 (1) ◽  
pp. 1195-1214 ◽  
Author(s):  
W. Chefurka
Keyword(s):  
Electron Transport ◽  
Oxidative Phosphorylation ◽  
Respiratory Chain ◽  
Transport System ◽  
Heart Muscle ◽  
Rat Heart ◽  
Complete Inhibition ◽  
Muscle Preparation ◽  
Rat Heart Mitochondria ◽  
Stimulation Of

The effects of inhibition of the electron transport system on the stimulation of the ATP-ase reaction in liver and rat-heart mitochondria by dinitrophenol were studied. Cyanide at concentrations 10−3M and higher effectively reduced the stimulation of ATP-ase by dinitrophenol. A similar but less striking inhibition was observed for rat-heart sarcosomes. This ATP-ase reaction was also inhibited in the presence of 10−4M cyanide with glutamate, β-hydroxybutyrate, DPNH, and succinate as reductants of the respiratory chain. Anaerobiosis also caused a substantial decrease in the ATP-ase reaction. In all instances, complete inhibition of the ATP-ase reaction could not be achieved when the respiratory chain was reduced. The magnesium-stimulated ATP-ase of rat-heart sarcosomes, of aged mitochondria, and of the Keilin–Hartree heart-muscle preparation was insensitive to reduction of the carriers suggesting that this reaction may constitute only part of the total ATP-ase reaction. The compatability of the various mechanisms of oxidative phosphorylation with these results is discussed.

The alteration of mitotic events by ionophore A23187 and carbonyl cyanide n-chlorophenylhydrazone

1985 ◽  
Vol 75 (1) ◽  
pp. 347-355
Author(s):  
M.L. Ziegler ◽  
J.E. Sisken ◽  
S. Vedbrat
Keyword(s):  
Oxidative Phosphorylation ◽  
Intracellular Calcium ◽  
Calcium Ions ◽  
Hela Cells ◽  
Cytosolic Calcium ◽  
Ionophore A23187 ◽  
Chromosome Movement ◽  
Low Concentrations ◽  
Carbonyl Cyanide ◽  
Stimulation Of

A large quantity of published work indicates that calcium ions may be involved in the regulation of mitotic events and recent reports suggest that the onset of chromosome movement is dependent upon a transient increase in free cytosolic calcium ions. In this paper we examine the effects of two agents known to perturb intracellular calcium pools on mitosis in HeLa cells. These were the calcium-selective ionophore A23187 and carbonyl cyanide n-chlorophenylhydrazone (CCCP), which is a protonophoric inhibitor of oxidative phosphorylation. Owing to a stimulation of glycolysis, the latter agent does not decrease intracellular ATP in HeLa but does cause mitochondria to release calcium ions. Our data show that, at low concentrations, both agents prolong metaphase but differ in their effects on anaphase and cytokinesis. Studies with chlorotetracycline, a commonly used probe for membrane-associated calcium, verify that these agents do affect calcium pools under the conditions of our experiments. The data presented are consistent with the idea that increased cytosolic calcium levels can directly or indirectly affect mitotic events but, contrary to other suggestions, cause a prolongation of metaphase, i.e. they delay the onset of chromosome movement.

Sign in / Sign up

Export Citation Format

Share Document