Juanita Bustamante

..We can conclude that a decreased motor performance observed in the hangover group of animals could be associated with brain cortex mitochondrial dysfunction and the resulting impairment of its energetic metabolism...

..In addition, in vitro studies performed in mitochondria from sham animals showed that mitochondrial permeability transition (MPT) could be a mitochondrial mediator of the apoptotic signaling in the presence of NH(4) (+) and calcium...

..This is mediated through mitochondrial events, associated with an evident decrease in DeltaPsi(m), cytochrome c release and caspase 3 activation...

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..Meanwhile, other thymocyte apoptotic pathways, such as those induced by MPS or etoposide, seem to centrally involve mitochondria but not endoplasmic reticulum...

..All these results seems to be clearly related with the reversible and concentration-dependent attenuation of the respiratory chain by NO...

..During rat growth, the respiratory function seems to be modulated by NO produced by the different NOS enzymes: nNOS, eNOS and mtNOS present in the cytosol and in the mitochondria...

..Regulation of mtNOS activity by membrane potential makes mtNOS a regulable enzyme that in turn regulates mitochondrial O2 uptake and H2O2 production...

..It is concluded that the moderate increase in plasma ammonia that followed portal hypertension was the potential primary cause of the observed alterations...

..However, the loss of keratinocyte mitochondrial function generated by UVB, as well as its kinetics, has not been characterized completely...

..This work provides evidence that in the studied conditions, dopamine modifies mitochondrial function by a nitric oxide-dependent pathway...

..It may be concluded that the reaction of mitochondrial ubiquinol with peroxynitrite is part of a complex regulatory mechanism with implications for mitochondrial function and integrity...

..Results indicate that chlorpromazine inhibits brain mtNOS activity in vitro and can exert the same action in vivo...

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..Inhibition of Complex I activity by peroxynitrite may have critical implications for energy supply in tissues such as the brain, whose mitochondrial function depends largely on the channelling of reducing equivalents through Complex I...

..Our results suggest that in vitro effects of deprenyl on mitochondrial function can occur through two different mechanisms, involving nitric oxide synthase inhibition and decreased hydrogen peroxide production...

..Preincubation of thymocytes with NOS inhibitors (NG-methyl-L-arginine and L-Nomega-nitro-L-arginine methylester) halted the whole process through inhibition of mitochondrial and endoplasmic reticulum NOS activities and of DNA laddering...

..The observations suggest that NO-mediated pathways contribute to pacemaker heart activity, likely through the NO steady-state levels in the right atrium and the whole heart...

..We conclude that high altitude triggers a physiological adaptive response that upregulates heart mtNOS activity and is associated in an opposed manner with the serum levels of testosterone and estradiol...

..Nitric oxide and H(2)O(2) constitute signals for metabolic control that are involved in the regulation of cellular processes, such as proliferation and apoptosis...

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..The aim of the current study was to investigate the effect of UVB irradiation in hairless mice skin...

..This action was determined by in situ gastric mucosa chemiluminescence and by tissue antioxidant content...

..Mitochondrial aging by oxyradical- and peroxynitrite-induced damage would occur through selective mtDNA damage and protein inactivation, leading to dysfunctional mitochondria unable to keep membrane potential and ATP synthesis...

..It is apparent that NO and O2- production by human mononuclear cells may constitute the basis of intercellular signaling and cell toxicity...

..An intramitochondrial steady state concentration of about 2 nM ONOO- was calculated, taking into account the rate constants and concentrations of ONOO- coreactants...

..This inhibition does not seem to be caused by increased NO or ONOO- formation...

..Septic shock and endotoxemia produce muscle dysfunction and oxidative stress due to increased steady state concentrations of reactive oxygen and nitrogen species...

..Results suggest that in chronic hypoxia there is a lower rate of generation of active oxygen species in liver, leading to a decreased steady-state concentration of singlet oxygen...

..Those patients who received antioxidant therapy benefited by less oxidative stress and mitochondrial damage...

..Incubation of slices with 10(-5)M I-HO-A caused a 46% decrease in PB125I formation and addition of actinomycin D or puromycin failed to alter this effect.(ABSTRACT TRUNCATED AT 250 WORDS)..

..Results support the putative role of mtNOS in the mechanism involved...