Hypoxic vasoconstriction is important for lung ventilation/perfusion matching. The mechanism of hypoxic vasoconstriction remains elusive. Arachidonic acid is released from hypoxic tissues; possibly vasoconstricting arachidonate metabolites are involved in hypoxic pulmonary vasoconstriction. Data are presented that consider (a) lipoxygenase product(s) as "local," which could be involved in the h...

Phospholipid metabolism was studied in rat myocardial slices that were incubated under normoxia or hypoxia for up to 24 hours. Phospholipid degradation was prominent in hypoxic myocardium, particularly phosphatidylcholine, which markedly decreased after 24 hours of hypoxia. In contrast, lysophosphatidylcholine increased. The mechanism of phospholipid degradation in hypoxic myocardium was studie...

Brief episodes of cerebral hypoxia-ischemia cause transient ischemic tolerance to subsequent ischemic events that are otherwise lethal. This study was conducted to evaluate the protective effect of hypoxic preconditioning on hypoxic-ischemic injury in the neonatal rat and the persistence of a protective window after hypoxic preconditioning. The rats were preconditioned with hypoxia (8% oxygen, ...

In this study, we investigated possible separate effects of H+ ions and CO2 on hypoxic sensitivity in humans. We also examined whether hypoxic sensitivity, conventionally defined as the ratio of (hypoxic - normoxic) ventilation over (hypoxic - normoxic) Hb oxygen saturation can also be estimated by taking the ratio (hypoxic - normoxic) ventilation over (logPa(O2) hypoxia - logPa(O2) normoxia), ...

BACKGROUND Myoclonus may occur after hypoxia. In 1963, Lance and Adams described persistent myoclonus with other features after hypoxia. However, myoclonus occurring immediately after hypoxia may demonstrate different syndromic features from classic Lance-Adams syndrome (LAS). The aim of this review is to provide up-to-date information about the spectrum of myoclonus occurring after hypoxia wit...

BACKGROUND Glutamate has been implicated in the pathophysiology of acute hypoxic-ischemic encephalopathy. Glutamine synthetase is an enzyme found in astrocytes that converts glutamate to its nontoxic analogue, glutamine. The present study tests the hypothesis that brain glutamine synthetase activity increases in response to acute hypoxic-ischemic insults and not in response to chronic hypoxia-i...

The abundance of neuropeptide Y (NPY)-, vasoactive intestinal polypeptide (VIP)-, substance P (SP)-, and calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers in the carotid body was examined in chronically hypercapnic hypoxic rats (10% O2 and 6-7% CO2 for 3 months), and the distribution and abundance of these four peptidergic fibers were compared with those of previously reported ...

effects of acute systemic hypoxia on the cardiovascular system (cys) and respiration of spontaneously breathing cats were studied in two conditions. 1): hypoxic air (6-8% 02 in n2) was given to the animal to induce systemic hypoxia for 20 minutes. hyperventilation at this condition lowered arterial c02 tension (pac02 hypocapnia). 2): in the second run, induction of hypocapnia was prevented by a...

Altitude training is to enhance performance. The fundamental theory behind altitude in that, by exposing an athlete environmental that low oxygen, (Hypoxic), the body will eventually adapt and improve its efficiency (acclimatized). In volley ball it necessary clarify effect of on hematological variables, increased oxygen intake, fitness factor, molecular adaptations, genetic adaptations acclima...

Exercise exacerbates acute mountain sickness. In infants and small mammals, hypoxia elicits a decrease in body temperature (Tb) [hypoxic thermal response (HTR)], which may protect against hypoxic tissue damage. We postulated that exercise would counteract the HTR and promote hypoxic tissue damage. Tb was measured by telemetry in rats (n = 28) exercising or sedentary in either normoxia or hypoxi...