| Autor: |
A. David Edwards, Chris E. Cooper, John S. Wyatt, Guy C. Brown, Ernest B. Cady, E. Osmund R. Reynolds, Vincent Kirkbride, A Lorek, Juliet Penrice, H Owen-Reece |
| Rok vydání: |
1994 |
| Předmět: |
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| Zdroj: |
Magma: Magnetic Resonance Materials in Physics, Biology, and Medicine. 2:441-444 |
| ISSN: |
1352-8661 |
| DOI: |
10.1007/bf01705293 |
| Popis: |
In vivo proton (1H) magnetic resonance spectroscopy (MRS) can measure cerebral metabolite concentrations and nuclear relaxation times. Function of the sodium (Na+)/potassium (K+) pump in cell membranes depends on adequate adenosine triphosphate (ATP) levels: intracellular Na+ is normally extruded in exchange for extracellular K+. Low ATP will cause pump dysfunction and loss of K+ accompanied by influx of Na+and water. Raised intracellular water may increase molecular mobility and this might be detectable as increased apparent transverse relaxation times (T 2's).1H-MRS of the brains of newborn piglets during acute hypoxia-ischemia revealed enigmatic increases in the peak area of creatine + phosphocreatine (Cr) relative to those of choline-containing compounds (Cho) andN-acetylaspartate (NAA). Interleaved1H and phosphorus (31P) MRS showed that theT 2's of both Cr and lactate (Lac) increased during acute hypoxia-ischemia and these changes correlated with reductions in nucleotide triphosphate (NTP; largely ATP). Within 50 h of metabolic recovery from the primary insult, as delayed energy failure developed, theT 2's of Cho, Cr, NAA, and Lac increased greatly. TheseT 2 changes also correlated with NTP depletion. These observations demonstrate important relationships betweenT 2's and function of the ATP-dependent Na+/K+ pump. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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