Alterations in purine nucleotides and phospholipids during in vivo
ischemia and reperfusion in rat skeletal muscle. effect of
ascorbate.
Lagerwall, K., B. Madhu, P. Daneryd, T. Scherst[umlaut]an, and B.
Soussi.
Bioenergetics Group, Wallenberg Laboratory & Lundberg Laboratory
for Bioanalysis, Department of Surgery, University of
G[umlaut]uteborg, Sahlgrenska sjukhuset, S-413 45 G[umlaut]uteborg,
Sweden
APStracts 3:0287H, 1996.
The effect of intravenously administered ascorbate on the ischemic and
reperfused rat skeletal muscle was investigated. Purine nucleotides
and phospholipids in skeletal muscle from rats subjected to 4 h
ischemia followed by 1 h reperfusion were analyzed by high
performance liquid chromatography (HPLC). In addition, adenosine
triphosphate (ATP), phosphocreatine (PCr), inorganic phosphate (Pi)
and phosphomonoesters (PME) were analyzed by 31P nuclear magnetic
resonance (NMR) at 202.4 MHz, and individual PME such as glucose-6
-phosphate (G6P) and inosine monophosphate (IMP) were quantified. PCr
and ATP were exhausted after 4 h ischemia and recovered poorly upon
reperfusion in the soleus and tibialis muscle of untreated rats.
Postischemic reperfusion resulted in significant loss of cardiolipin.
Treatment with 55 mM ascorbate resulted in total restoration of PCr
during reperfusion, and ATP recovered to 42% of control in the
soleus. Recovery was improved in the tibialis as well, and the
cardiolipin decrease was limited. A lower ascorbate concentration (5
mM) did not enhance postischemic recovery. Our findings show that a
high dose of ascorbate improves the energetic state of rat skeletal
muscle during postischemic reperfusion, probably due to its
antioxidant function.
Received 24 July 1996; accepted in final form 8 July 1996.
APS Manuscript Number H704-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 25 July 1996