HeLa and PANC-1 cells were exposed to conflicting signals promoting anaerobic or aerobic energy-generating processes and their viability, cell numbers and the ability of HeLa cells to form colonies were assessed. Under conventional aerobic cell culture with 5% CO(2), dichloroacetate (DCA), an inhibitor of the enzyme pyruvate dehydrogense kinase with subsequent stimulation of pyruvate dehydrogen...

Since the initial observations made at the beginning of the last century, it has been established that solid tumors contain regions of low oxygenation (hypoxia). Tumor cells can survive in these hypoxic conditions and are a major factor in tumor radioresistance. This significance has resulted in hypoxia becoming the most cited biological topic in translational radiation oncology. Identifying hy...

Hypoxia is a key determinant of tumor aggressiveness, yet little is known regarding hypoxic global gene regulation in vivo. We used the hypoxia marker EF5 coupled with laser-capture microdissection to isolate RNA from viable hypoxic and normoxic regions of 9L experimental gliomas. Through microarray analysis, we identified several mRNAs (including the HIF targets Vegf, Glut-1, and Hsp27) with i...

Infants born premature experience hypoxic episodes due to immaturity of their respiratory and central nervous systems. This profoundly affects brain development and results in cognitive impairments. We used a mouse model to examine the impact of hypoxic rearing (9.5-10.5% O2) from postnatal day 3 to 11 (P3-P11) on GABAergic interneurons and the potential for environmental enrichment to ameliora...

Fish exposed to hypoxia develop decreased heart rate, or bradycardia, the physiological significance of which remains unknown. The general muscarinic receptor antagonist atropine abolishes the development of this hypoxic bradycardia, suggesting the involvement of muscarinic receptors. In this study, we tested the hypothesis that the hypoxic bradycardia is mediated specifically by stimulation of...

Electrophysiological responses to transient hypoxia were studied in neocortical brain slices from adult gerbils. Evoked responses and direct current (DC) potentials were recorded in layer III of the parietal cortex under normoxic and hypoxic conditions. The excitatory synaptic component of the evoked waveform was identified by its sensitivity to calcium and 6,7-dinitroquinoxaline-2,3-dione (DNQ...

The cytotoxic effects of anthracyclines and other chemotherapeutic agents were examined in normally aerated and hypoxic Sarcoma 180 and EMT6 tumor cells in vitro. Adriamycin, daunomycin, and mitomycin C were selectively toxic to hypoxic Sarcoma 180 cells. The augmented sensitivity was not the result of an increase in susceptibility of oxygen-deprived cells toward antitumor agents in general. 1,...

Background: Ghrelin is a peptide predominantly produced by the stomach. Recent studies have shown its protective roles and plasma alterations during hypoxia. Objectives: The aim of this study was to assess the effects of an exogenous administration of ghrelin on body weight and blood hematocrit during chronic hypoxia. Materials and Methods: Twenty four adult male Wistar rats were divided random...

AIM To evaluate the incidence, etiology, and predictors of mortality of severe hypoxic hepatitis. METHODS We used computerized patient records to identify consecutive cases of severe hypoxic hepatitis admitted to a tertiary hospital in Singapore over a one-year period. We defined severe hypoxic hepatitis as elevation of serum transaminases more than 100 times upper limit of normal in the clin...