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Acute mountain sickness is caused by sub-acute hypoxia in healthy individuals going rapidly to altitude. Both tissue hypoxia in vitro and whole-body hypoxia in vivo have been found to promote the release of reactive oxygen species. Nitronyl nitroxide can trap free radicals such as ·NO or ·OH, and
Nitric oxide (NO) is a vasodilator that plays a role in blood flow and oxygen delivery. Acute hypoxia down regulates NO synthesis, a response that may exacerbate hypoxic stress by decreasing blood flow. This study was designed to test the hypotheses that pulmonary NO decreases upon acute exposure to
In a randomized, placebo-controlled, double-blind study, we tested a 4-week program in normobaric hypoxia that is commercially offered for the prevention of acute mountain sickness (AMS). Twenty-two male and 18 female healthy subjects [mean age 33 +/- 7 (SD) years] exercised 70 min, 3 x /week for 3
Intermittent hypoxia (IH) is a promising approach to induce acclimatization and hence lower the risk of developing acute mountain sickness (AMS). We hypothesized that a short-term IH protocol in normobaric hypoxia (7 × 1 h to 4500 m) effectively increases the hypoxic ventilatory response (HVR) and
The study was carried out on 17 healthy males aged 20-27 years subjected for 15 minutes to submaximal effort on a cycle ergometer (Elema-Schonander) under conditions of breathing ambient atmospheric air or a helium-oxygen mixture (20% O2 + 80% He) and under hypobaric pressure simulating an altitude
The objective of the presented studies is to attempt an evaluation of heart rate (HR) and heart rate variability (HRV) regulatory mechanisms in the presence of autonomous nervous system (ANS) components in transient exposure to high altitude hypoxia. During 24 hrs including a stay in hypobaria, the
The purpose of this study was to test an ascent program for ideal psychological adaptation to high altitudes. A psychological approach was used to test a model describing a gradual step-by-step ascent. Seven subjects spent nine days between 3,500 m and 4,400 m altitude, followed by eight days
High altitude hypoxia is an important factor to affect fetal development during pregnancy. In the special environment, maternal physiological functions are regulated to maintain the maternal and fetal homeostasis, so that limited oxygen is to meet the needs of fetal growth and development. In this
Experiments on rats exposed to intense exercise and high-altitude hypoxia have shown the reduction in physical efficiency and in the training effect of muscle loads as compared to the same characteristics examined under the conditions of plain. Electron microscopy of rat skeletal muscle fibers has
Adaptation to simulated altitude hypoxia was followed by a significant increase of the degree of retention of active avoidance of the conditioned reflex. Twenty four hours after the reflex elaboration the adapted rats required only half of conditioned and unconditioned stimulus combinations in the
In the article, findings of the studies of white blood in healthy subjects during a short-term adaptation to high altitude (per. Tuya-Ashu, 3200 m), are discussed. A 40-day adaptation of healthy people has led to positive shifts: an increase of the number of leukocytes with prevalence of the
The Tibetan cashmere goat is one of the main goat breeds used by people living in the plateau. It exhibits the distinct phenotypic characteristics observed in lowland goats, allowing them to adapt to the challenging conditions at high altitudes. It provides an ideal model for understanding the
Pulmonary hemodynamics in anesthetized rats was studied during long-term residence (2,5 and 10 months) at high altitude (3,200 m, Tien Shan). Transbronchial regional electroplethysmography and catheterization of pulmonary artery was used. It has been shown that at all periods of adaptation there was
We hypothesized that an expiratory resistance and dead space (ER/DS) mask, a version of which was previously shown to partially alleviate sleep-disordered breathing and headache severity during acute normobaric hypoxia (Patrician et al.), would exhibit similar results in conditions of hypobaric
It was shown in experiments on intact male rabbits that moderate-altitude hypoxia causes over-stress of the cardiomyocyte energy-producing apparatus in unadapted animals. Acute infusion of verapamil leads to a high mortality rate among these animals, whereas among aborigines of moderate and low