Effects of hyperglycemia or hypoglycemia on brain cell membrane function and energy metabolism during the immediate reoxygenation-reperfusion period after acute transient global hypoxia-ischemia in the newborn piglet

Citation
Ws. Park et al., Effects of hyperglycemia or hypoglycemia on brain cell membrane function and energy metabolism during the immediate reoxygenation-reperfusion period after acute transient global hypoxia-ischemia in the newborn piglet, BRAIN RES, 901(1-2), 2001, pp. 102-108
Citations number
26
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences & Behavoir
Journal title
BRAIN RESEARCH
ISSN journal
0006-8993 → ACNP
Volume
901
Issue
1-2
Year of publication
2001
Pages
102 - 108
Database
ISI
SICI code
0006-8993(20010518)901:1-2<102:EOHOHO>2.0.ZU;2-4
Abstract
This study was done to determine the effects of hyperglycemia or hypoglycem ia on brain cell membrane function and energy metabolism during the immedia te reoxygenation-reperfusion period after hypoxia-ischemia (HI). Forty-five newborn piglets were divided randomly into four experimental groups: normo xia control (NC, n=9); HI/reoxygenation-reperfusion (RR) control (HC, n=11) ; HI/RR hyperglycemia (HE, n=12); and HI/RR hypoglycemia (HO, n=13) group. Animals were subjected to transient HI for 30 min followed by 2 h of RR. Ce rebral HI was induced by temporary but complete occlusion of bilateral comm on carotid arteries with surgical clips and simultaneous breathing with 8% oxygen. Glucose was unregulated in HC group, and controlled by modified glu cose clamp technique immediately after HI in HE (350 mg/dl) and HO (50 mg/d l) groups. During HI, heart rate, base deficit, glucose and lactate level i n the blood and cerebrospinal fluid increased, and arterial pH, oxygen satu ration and blood pressure decreased significantly in HC, HE and HO groups. During RR, these abnormalities returned to normal values, but lactic acidos is persisted especially in HO group. Cerebral Na+,K+-ATPase activity decrea sed, and lipid peroxidation products increased significantly in HC group th an in NC group, and these abnormalities were significantly aggravated in HE , but not in HO, group. Brain ATP and phosphocreatine levels in HE group we re significantly reduced compared to the corresponding values in NC, HC and HO groups. In summary, hyperglycemia, but not hypoglycemia immediately aft er HI interfered with the recovery of brain cell membrane function and ener gy metabolism. These findings suggest that post-hypoxic-ischemic hyperglyce mia is not beneficial and might even be harmful in neonatal hypoxic-ischemi c encephalopathy. (C) 2001 Elsevier Science B.V. All rights reserved.