Cumulative Effect of Repeated Brief Cerebral Ischemia
Abstract
The purpose of this grant is to investigate the metabolic and physiological factors determining the extent of ischemic damage in a model of brief repetitive ischemia. The model is intended to simulate the effects of Gz induced blackout experienced by fighter pilots undergoing high gravitational stress maneuvers. To achieve this goal a rat model was developed whereby ischemia could be induced remotely (under computer regulation) by inflation of occlusive cuff about the common carotid artery of the rat. Metabolic parameters were determined by performing in vivo NMR measurements throughout the repetitive ischemic insult. The non-destructive nature of the NMR measurement permits complete time courses to be monitored in each animal thereby minimizing animal variability. NMR measurements of metabolite content are then used in conjunction with histologic evaluations of neuronal death to assess which metabolic factors have the strongest influence on ischemic damage. During the past year we have completed our studies: (a) investigating the correlations between EEG, phosphocreatine (PCr), adenosine triphosphate (ATP), inorganic phosphate (P), pH and lactate as a function of increasing ischemic severity in our model of brief repetitive ischemia and (b) characterizing substrate utilization and lactate clearance curves using the same model. These experiments have been performed in the rat brain using the repetitive ischemia model with in vivo NMR to measure metabolite content.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 31, 1993
- Accession Number
- ADA267155
Entities
People
- Hoby Hetherington
Organizations
- University of Alabama at Birmingham