To investigate regulation of anaerobic carbohydrate catabolism in anoxia-tolerant plant tissue, rate of alcoholic fermentation and maximum catalytic activities of four key enzymes were assessed in coleoptiles of two rice cultivars that differ in tolerance to anoxia. The enzymes were ATP-dependent phosphofructokinase (PFK), pyrophosphate-dependent phosphofructokinase (PFP), pyruvate decarboxylas...

Volume regulation of C6 glial cells was studied in anoxia in vitro to improve the understanding of ischemic cell swelling in the brain. Contrary to in vivo conditions, anoxia or anoxia plus iodoacetate for additional inhibition of anaerobic energy metabolism did not induce glial swelling. However, intracellular K+ was markedly decreased while intracellular Na+ increased. Induction of energy fai...

The influence of ATP-sensitive K+ channels (K(ATP) channels) on cardiac performance during anoxia and reoxygenation was investigated in two species of fish showing different cardiac responses to anoxia. Force production in isometrically contracting ventricular muscle preparations from yellowtail flounder is potentiated at the onset of anoxia, while force immediately declines in Atlantic cod pre...

The aim of this review was to discuss and evaluate the impact of oxygen deficiency on the cellular level on organ reperfusion. Tissue anoxia can be divided into three groups: normal-flow, low-flow and no-flow anoxia. The outcome after a normotoxic reperfusion is different for these three groups. The author presents the technologies for local measurements of tissue oxygen partial pressure, local...

Depression of the production and consumption of cellular energy appears to be a prerequisite for the survival of prolonged bouts of anoxia. A correlation exists between the degree of metabolic depression under anoxia and the duration of anoxia tolerance. In the case of brine shrimp (Artemia franciscana) embryos, oxygen deprivation induces a reversible quiescent state that can be tolerated for s...

Acute life-threatening situations are particularly critical when superimposed on chronic diseases. The objective of this study was the assessment of heart rate (HR) dynamics during episodes of acute anoxia superimposed on a rat model of chronic pulmonary hypertension. In 10 adult Wistar rats, five weeks after pulmonary hypertension induction with Monocrotaline, we analysed eight 1-min HR segmen...

The effect of a hypoxic pre-treatment (HPT) on improving tolerance to prolonged anoxia conditions in two contrasting Vitis species (V. riparia, anoxia tolerant; V. rupestris, anoxia sensitive) was evaluated. The energy economy of root cells was studied by measuring heat production, the activity of pyruvate decarboxylase (PDC) and alcohol dehdrogenase (ADH), ethanol and ATP production, and K(+) ...

Facultative anaerobiosis occurs widely across phylogeny and comparative studies with multiple animal models are identifying conserved molecular mechanisms that support anoxia tolerance. Our studies of freshwater turtles have analyzed metabolic, signal transduction and gene expression responses to anoxia. A key mechanism is reversible protein phosphorylation, which provides coordinate suppressio...

-A data retrieval procedure is used to process observed dissolved oxygen (DO) concentrations in the Chesapeake Bay to obtain information on the intensity or degree of anoxia, and to explore optimal DO-thresholds to define the degree of anoxia. The method consists of a series of processes, such as data interpolation, pattern mining, feature transformation, uncertainty management, and verificatio...

To identify factors responsible for the down-regulation of mitochondrial biosynthetic processes during anoxia in encysted Artemia franciscana embryos, the effects of oxygen limitation and pH on protein synthesis were investigated in isolated mitochondria. At the optimal pH of 7.5, exposure of mitochondria to anoxia decreases the protein synthesis rate by 79%. Rates were suppressed by a further ...