Hyperglycemia and the rate of lactic acid accumulation during cerebral ischemia in developing animals: in vivo proton MRS study.
During cerebral ischemia, hyperglycemia has a deleterious effect upon the adult brain but not the neonatal brain. This phenomenon may be related to the fact that hyperglycemia in adult animals subjected to cerebral ischemia raises the ischemic accumulation of lactate by as much as 10-fold. The purpose of this study was to determine whether hyperglycemia during cerebral ischemia produces a similar increase in the rate of lactic acid accumulation in developing animals. Data from in vivo proton magnetic resonance spectroscopic experiments showed that blood glucose concentration did not affect the rate of lactic acid accumulation during cerebral ischemia in either the neonatal dog or juvenile rabbit. The lack of increase in the ischemic rate of lactic acid accumulation during hyperglycemia in the developing animal contrasts sharply with the marked effect of blood glucose concentration upon the rate of lactic acid accumulation in the adult animal. Differences in the total amount of lactic acid formed and the rate at which it is accumulated may contribute, in part, to the greater tolerance of the young animal to cerebral ischemia.
Young
R S
RS
Department of Pediatrics, Yale University School of Medicine, New Haven, Conn. 06510.
Petroff
O A
OA
Aquila
W J
WJ
Cheung
A
A
Gore
J C
JC
D000375:Aging / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D004285:Dogs; D006943:Hyperglycemia / Q000150:complications / Q000378:metabolism*; D002546:Ischemic Attack, Transient / Q000150:complications / Q000378:metabolism*; D007773:Lactates / Q000378:metabolism*; D019344:Lactic Acid; D009682:Magnetic Resonance Spectroscopy; D011817:Rabbits
D001786:Blood Glucose; D007773:Lactates; D019344:Lactic Acid