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Interaction between reactive oxygen species and nitric oxide in the microvascular response to systemic hypoxia
Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas 66160 Systemic hypoxia results in oxidative stress due to a change in the reactive oxygen species (ROS)-nitric oxide (NO) balance. These experiments explored two mechanisms for the altered RO...
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Published in: | Journal of applied physiology (1985) 2002-10, Vol.93 (4), p.1411-1418 |
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Main Authors: | , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
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Summary: | Department of Molecular and Integrative Physiology,
University of Kansas Medical Center, Kansas City, Kansas 66160
Systemic hypoxia
results in oxidative stress due to a change in the reactive oxygen
species (ROS)-nitric oxide (NO) balance. These experiments explored two
mechanisms for the altered ROS-NO balance: 1 ) decreased NO
synthesis by NO synthase due to limited O 2 substrate
availability and 2 ) increased superoxide generation. ROS
levels and leukocyte adherence in mesenteric venules of rats during
hypoxia were studied in the absence and presence of an NO donor
[spermine NONOate (SNO)] and of the NO precursor
L -arginine. We hypothesized that if the lower NO levels
during hypoxia were due to O 2 substrate limitation,
L -arginine would not prevent hypoxia-induced microvascular
responses. Graded hypoxia (produced by breathing 15, 10, and 7.5%
O 2 ) increased both ROS (123 ± 6, 148 ± 11, and 167 ± 3% of control) and leukocyte adherence. ROS levels during breathing of 10 and 7.5% O 2 were significantly attenuated
by SNO (105 ± 6 and 108 ± 3%, respectively) and
L -arginine (117 ± 5 and 115 ± 2%,
respectively). Both interventions reduced leukocyte adherence by
similar degrees. The fact that the effects of L -arginine were similar to those of SNO does not support the idea that NO generation is impaired in hypoxia and suggests that tissue NO levels
are depleted by the increased ROS during hypoxia.
mesenteric venules; leukocyte adherence; superoxide; dihydrorhodamine |
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ISSN: | 8750-7587 1522-1601 |
DOI: | 10.1152/japplphysiol.00251.2002 |