Reduction of hyperthermic ischemic acidosis by a conditioning event in cats.
We investigated the effects of multiple episodes of cerebral ischemia on intracellular brain pH using in vivo phosphorus-31 nuclear magnetic resonance spectroscopy. Four cats were subjected to two 16-minute episodes of complete global cerebral ischemia 6 hours apart; the second episode occurred under hyperthermic conditions (mean +/- SD body temperature 40.8 +/- 0.4 degrees C). Intracellular pH in these four cats was compared with that in nine cats subjected to a single 16-minute episode of complete global cerebral ischemia under hyperthermic conditions (mean +/- SD body temperature 40.6 +/- 0.2 degrees C). Intracellular pH during hyperthermic recirculation was significantly (p less than 0.03) greater in cats subjected to a previous ischemic event than that in cats subjected to only a single hyperthermic ischemic event. We speculate that the induction of heat shock proteins by an initial ischemic event may protect brain tissue from further ischemic insult.
Chopp
M
M
Department of Neurology, Henry Ford Hospital, Detroit, MI 48202.
Tidwell
C D
CD
Lee
Y J
YJ
Knight
R
R
Helpern
J A
JA
Welch
K M
KM
D000138:Acidosis / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D002415:Cats; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006979:Hyperthermia, Induced; D009682:Magnetic Resonance Spectroscopy
D006360:Heat-Shock Proteins