title: On-line monitoring of striatum glucose and lactate in the endothelin-1 rat model of transient focal cerebral ischemia using microdialysis and flow-injection analysis with biosensors.
abstract: In vivo studies on cerebral glucose and lactate metabolism following a brain insult require fast and sensitive monitoring techniques. Here we report on-line monitoring of ischemic events and metabolic changes following reperfusion in striatum of freely moving rats subjected to endothelin-1 (60-240 pmol) induced, transient focal cerebral ischemia using slow microdialysis (0.5 microl/min), fast sampling (every minute) and flow-injection analysis with biosensors for glucose and lactate. The high-time resolution provides detailed information on lactate rise times and duration of low glucose. In rats, developing large striatal lesions, lactate increased from 1.0 +/- 0.1 to 4.2 +/- 0.7 mM within 37 +/- 1 min, whereas glucose dropped from 0.3 +/- 0.1 mM to below detection levels (<0.05 mM) for a period of 80 +/- 18 min. The lactate increase measured over a 2-h period after endothelin-1 infusion was highly correlated with striatal infarct size. In some rats oscillatory changes are observed which cannot be detected in traditional assays. The here-described monitoring technique applied in a clinically relevant rat model is a sensitive tool to study post-ischemic energy metabolism, effects of therapeutic interventions and its relationship with histological outcome.
authors.affiliation: Anatomy and Neurobiology, Institute of Medical Biology, University of Southern Denmark, Odense, Denmark. jbgramsbergen@health.sdu.dk
authors.forename: Jan Bert
authors.initials: JB
authors.lastname: Gramsbergen
authors.forename: Jane
authors.initials: J
authors.lastname: Skjøth-Rasmussen
authors.forename: Camilla
authors.initials: C
authors.lastname: Rasmussen
authors.forename: Kate Lykke
authors.initials: KL
authors.lastname: Lambertsen
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002544:Cerebral Infarction / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D003342:Corpus Striatum / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D019332:Endothelin-1 / Q000009:adverse effects; D004734:Energy Metabolism / Q000502:physiology; D017022:Flow Injection Analysis; D005947:Glucose / Q000032:analysis* / Q000378:metabolism; D002546:Ischemic Attack, Transient / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D019344:Lactic Acid / Q000032:analysis* / Q000378:metabolism; D008297:Male; D017551:Microdialysis / Q000295:instrumentation / Q000379:methods*; D009448:Neurochemistry / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors; D015854:Up-Regulation / Q000187:drug effects / Q000502:physiology
chemical_list: D019332:Endothelin-1; D019344:Lactic Acid; D005947:Glucose