Hypoxia glucose

Brain Metabolic Indicators of Hypoxia Glucose and Ketone Body Transporters... 

Phase II begins 60 minutes into the seizure, and the patient begins to decompensate. The patient may become hypotensive, and cerebral blood flow may be compromised. Glucose may be normal or decreased, and hyperthermia, respiratory deterioration, hypoxia, and ventilatory failure may develop. 

Airley R, Loncaster J, Davidson S et al (2001) Glucose transporter glut-1 expression correlates with tumor hypoxia and predicts metastasis-free survival in advanced carcinoma of the cervix. Clin Cancer Res 7 928-934... 

Nakaya H, Kimura S, Kanno M. Intracellular K + and Na+ activities under hypoxia, acidosis, and no glucose in dog hearts. Am J Physiol 1985 249 H1078-H1085... 

It enhances cholinergic transmission and improves cerebral microcirculation in ischemic regions. It protects the neurons against hypoxia disturbance of glucose metabolism. 

In addition to ions, other small molecules have been described to play an important physiological and pathophysiological role in the regulation of gap junctional resistance. Thus, ATP acts as an important regulator. In 1979 Wojtcak described that hypoxia in glucose free solution resulted in a rise in Rj in cow ventricular trabeculae indicating that the intracellular ATP content... 

Fig. 20. Stimulus-response interval in guinea pig papillary muscle under normoxic and hypoxic conditions. Hypoxia was concomitted with glucose-free superfusion. Note the significant increase in the stimulus-response interval after 12 minutes of hypoxia. 

Hypoxia is a deficiency of oxygen needed to maintain cellular homeostasis. It may be caused by a reduction in blood supply, namely ischemia, decreased cardiopulmonary function, and diminished oxygen-carrying capacity of the blood. Subsequent oxygen deficiency in tissues leads to depressed aerobic metabolism and, thus, insufficient ATP synthesis. Reductions in blood flow also exacerbate oxygen deprivation by impairing delivery of nutrients, such as glucose, and the removal of metabolic wastes, such as C02, from affected cells. 

Oxygen is normally readily available to all reasonably well-perfused tissues, but deep inside organs such as the liver, especially the centrilobular area (see chap. 6), there will be a reduction in the oxygen concentration. This is clearly important when both oxidative and reductive pathways are available for a particular substrate. Therefore, as conditions in a particular tissue become more anaerobic, reductive pathways will become more important. This is well illustrated by the metabolism of halo thane where, in the rat, hypoxia will increase reductive metabolism and hepa to toxicity (see chap. 7). Glutathione is an extremely important cofactor, involved in both protection and conjugation. It may be depleted by both of these processes, or under certain circumstances, such as hereditary glucose-6-phosphate deficiency in man, supply may be reduced (see chap. 5). This will clearly influence toxicity, and there are a number of examples discussed in chapter 7 in which it is important. 

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