Abstract. The exact time profile of superoxide generation during anoxia-reoxygenation and ischemia-reperfusion was assessed in the feline cerebral cortex in vivo using a chemiluminescence technique with a probe specific for superoxide, 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA). MCLA solution was superfused on the cortex throughout the protocol, and MCLA chem...

In the brain of most vertebrates, anoxia or ischaemia rapidly causes a fall in ATP levels and in the activity of the Na + /K + pump, resulting in general depolarization followed by a cascade of catastrophic events (Hansen, 1985; Hochachka, 1986). By contrast, the brain of freshwater turtles survives many hours of complete anoxia at 25°C. Hence, the turtle brain has become the archetype of an an...

The relationship between cardiac energy metabolism and the depression of myocardial performance during oxygen deprivation has remained enigmatic. Here, we combine in vivo (31)P-NMR spectroscopy and MRI to provide the first temporal profile of in vivo cardiac energetics and cardiac performance of an anoxia-tolerant vertebrate, the freshwater turtle (Trachemys scripta) during long-term anoxia exp...

In severe hypoxia the breathing frequency is modulated in a biphasic manner: an initial increase (augmentation) is followed by a depression and cessation of breathing (apnea). Using a mouse slice preparation that contains the functional respiratory network, we aimed at identifying the neurons responsible for this frequency modulation. Whole-cell patch recordings revealed that expiratory neurons...

Citation: Léniz B, Murillo AA, Ramírez-Flandes S and Ulloa O (2017) Diversity and Transcriptional Levels of RuBisCO Form II of Sulfur-Oxidizing γ-Proteobacteria in Coastal-Upwelling Waters with Seasonal Anoxia. Front. Mar. Sci. 4:213. doi: 10.3389/fmars.2017.00213 Diversity and Transcriptional Levels of RuBisCO Form II of Sulfur-Oxidizing γ-Proteobacteria in Coastal-Upwelling Waters with Season...

Endosperms from castor beans (Ricinus communis) germinated for 0 to 6 days were exposed to anoxia for 0 to 15 hours. Ethanol, the only alcohol detected by gas chromatography in the tissue, accumulates to a concentration of 15 millimolar during the first 2 to 4 hours of anoxia and subsequently decreases. The absolute amount of ethanol varies from 10 micromoles per 5-day endosperm after 4 hours a...

The dramatic chromosome instability in certain tumors might reflect a synergy of spindle checkpoint defects with hypoxic conditions. In Caenorhabditis elegans and Drosophila melanogaster, spindle checkpoint activation has been implicated in the response to acute anoxia. The activation mechanism is unknown. Our analyses in D. melanogaster demonstrate that oxygen deprivation affects microtubule o...

The novel inhibitor of the reverse mode of the Na+/Ca2+exchanger (NCE) KB-R7943 (KB) was tested in isolated rat cardiomyocytes exposed to 80 min of simulated ischemia [substrate-free anoxia, extracellular pH (pHo) of 6.4] and 15 min of reoxygenation (pHo 7.4). At pHo 6.4, 20 μmol/l KB was required for complete inhibition of the reverse mode of NCE. Treatment with 20 μmol/l KB only during anoxia...

Some metazoans have evolved the capacity to survive severe oxygen deprivation. The nematode, Caenorhabditis elegans, exposed to anoxia (0 kPa, 0% O(2)) enters into a recoverable state of suspended animation during all stages of the life cycle. That is, all microscopically observable movement ceases including cell division, developmental progression, feeding, and motility. To understand suspende...

Hypoxic brain injury remains a major source of neurodevelopmental impairment for both term and preterm infants. The perinatal period is a time of rapid transition in oxygen environments and developmental resetting of oxygen sensing. The relationship between neural oxygen sensing ability and hypoxic injury has not been studied. The oxygen sensing circuitry in the model organism C. elegans is wel...