Effect of Acute Hypoxia Exposure on the Availability of A Adenosine Receptors and Perfusion in the Human Brain.

In animal studies it has been observed that the inhibitory neuromodulator adenosine is released into the cerebral interstitial space during hypoxic challenges. Adenosine's actions on the A adenosine receptor (AAR) protect the brain from oxygen deprivation and overexertion through adjustments in cerebral blood flow, metabolism, and electric activity. Using 8-cyclopentyl-3-(3-[F]fluoropropyl)-1-propylxanthine ([F]CPFPX), a PET tracer for the AAR, we tested the hypothesis that hypoxia-induced adenosine release reduces AAR availability in the human brain.

Electrocardiographic changes during sustained normobaric hypoxia in patients after myocardial infarction.

The safety of prolonged high-altitude stays and exercise for physically fit post-myocardial infarction (MI) patients is unclear. Myocardial tissue hypoxia and pulmonary hypertension can affect cardiac function and electrophysiology, possibly contributing to arrhythmias. We included four non-professional male athletes, clinically stable after left ventricular MI (three with ST-segment elevation MI and one with non-ST-segment elevation MI) treated with drug-eluting stents for single-vessel coronary artery disease.

Oral fructose intake does not improve exercise, visual, or cognitive performance during acute normobaric hypoxia in healthy humans.

Introduction: The ability to metabolize fructose to bypass the glucose pathway in near-anaerobic conditions appears to contribute to the extreme hypoxia tolerance of the naked-mole rats. Therefore, we hypothesized that exogenous fructose could improve endurance capacity and cognitive performance in humans exposed to hypoxia.

Methods: In a randomized, double-blind, crossover study, 26 healthy adults (9 women, 17 men; 28.