Journal article
Hyperthermia stimulates nitric oxide formation: electron paramagnetic resonance detection of .NO-heme in blood
Journal of applied physiology (1985), Vol.77(2), pp.548-553
08/01/1994
DOI: 10.1152/jappl.1994.77.2.548
PMID: 8002499
Abstract
Previous experiments from our laboratory have demonstrated that severe hyperthermia results in a selective loss of splanchnic vasoconstriction. Using electron paramagnetic resonance spectroscopy to scan whole blood samples collected in vivo from the portal vein and femoral artery of conscious unrestrained rats, we observed an increase in the concentration of spectroscopy-detectable species in portal venous blood of all heat-stressed animals. These spectra consisted of at least three distinct species: one with a broad feature having an effective g factor for the unpaired electron (g) of 2.06 assigned to the copper-binding acute phase protein ceruloplasmin, and two with narrower features that evolved at core temperatures > 39 degrees C representing a semiquinone radical and .NO-heme. This heat-induced signal displays the classic nitrogen triplet hyperfine structure (nitrogen hyperfine splitting constant = 17.5 gauss, centered at g = 2.012) that is consistent with a five-coordinate heme complex and is characteristic of an unpaired electron coupled to nitrogen in the ferrous .NO-heme adduct [(alpha 2+NO) beta 3+]2. The intensity of this signal increased approximately twofold as core temperature rose to > 39 degrees C, peaking 1 h post-heat exposure at greater than threefold basal concentration. This species was not seen in corresponding arterial blood samples. This is the first demonstration that whole body hyperthermia produces increased concentrations of radicals and metal binding proteins in the venous blood of the rat and suggests that severe hyperthermia stimulates an enhanced local release of .NO within the splanchnic circulation.
Details
- Title: Subtitle
- Hyperthermia stimulates nitric oxide formation: electron paramagnetic resonance detection of .NO-heme in blood
- Creators
- David M Hall - Department of Exercise Science, University of Iowa, Iowa City 52242Garry R Buettner - Department of Exercise Science, University of Iowa, Iowa City 52242Ronald D Matthes - Department of Exercise Science, University of Iowa, Iowa City 52242Carl V Gisolfi - Department of Exercise Science, University of Iowa, Iowa City 52242
- Resource Type
- Journal article
- Publication Details
- Journal of applied physiology (1985), Vol.77(2), pp.548-553
- DOI
- 10.1152/jappl.1994.77.2.548
- PMID
- 8002499
- ISSN
- 8750-7587
- eISSN
- 1522-1601
- Language
- English
- Date published
- 08/01/1994
- Academic Unit
- Radiation Oncology
- Record Identifier
- 9984046921502771
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