The Effect of Pentobarbital and Isoflurane on Glucose Metabolism in Thermally Injured Rat Brain

The effect of pentobarbital and isoflurane on cerebral glucose metabolism (CMRglc) was studied in thermally injured rat brain using quantitative autoradiography. In awake lesioned animals, CMRglc in cortical regions ipsilateral to the injury was reduced to 50% of normal while little if any decrease was observed in contralateral cortical regions and subcortical regions bilaterally. Treatment of lesioned animals with pentobarbital or isoflurane further reduced CMRglc, but more in the hemisphere contralateral to the injury than on the injured side. Thus, the side-to-side difference in cortical CMRglc present in the awake lesioned animals was abolished by the anesthetics. The results support the hypothesis that CMRglc depression associated with a focal cold injury is functional in nature. Reduction of metabolism by anesthetics in functionally depressed brain is limited by the decrease in CMRglc associated with the injury.

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Reproducibility of Cerebral Glucose Metabolic Measurements in Resting Human Subjects

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1988.91 ◽

1988 ◽

Vol 8 (4) ◽

pp. 502-512 ◽

Cited By ~ 89

Author(s):

Elsa J. Bartlett ◽

Jonathan D. Brodie ◽

Alfred P. Wolf ◽

David R. Christman ◽

Eugene Laska ◽

...

Keyword(s):

Glucose Metabolism ◽

Brain Metabolism ◽

Human Subjects ◽

Normal Subjects ◽

Time Of Day ◽

Cerebral Glucose Metabolism ◽

Whole Brain ◽

Positron Emission ◽

Subcortical Regions ◽

Regional Cerebral Glucose Metabolism

Positron emission tomography with 11C-2-deoxyglucose was used to determine the test-retest variability of regional cerebral glucose metabolism in 22 young normal right-handed men scanned twice in a 24-h period under baseline (resting) conditions. To assess the effects of scan order and time of day on variability, 12 subjects were scanned in the morning and afternoon of the same day (a.m.-p.m.) and 10 in the reverse order (p.m.-a.m.) with a night in between. The effect of anxiety on metabolism was also assessed. Seventy-three percent of the total subject group showed changes in whole brain metabolism from the first to the second measurement of 10% or less, with comparable changes in various cortical and subcortical regions. When a scaling factor was used to equate the whole brain metabolism in the two scans for each individual, the resulting average regional changes for each group were no mote than 1%. This suggests that the proportion of the whole brain metabolism utilized regionally is stable in a group of subjects over time. Both groups of subjects had lower morning than afternoon metabolism, but the differences were slight in the p.m.-a.m. group. One measure of anxiety (pulse at fun 1) was correlated with run 1 metabolism and with the percentage of change from run 1 to run 2. No significant run 2 correlations were observed. This is the first study to measure test-retest variability in cerebral glucose metabolism in a large sample of young normal subjects. It demonstrates that the deoxyglucose method yields low Intrasubject variability and high stability over a 24-h period.

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Effect of Phenytoin on Human Cerebral Glucose Metabolism

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1986.54 ◽

1986 ◽

Vol 6 (3) ◽

pp. 315-320 ◽

Cited By ~ 52

Author(s):

William H. Theodore ◽

Dikran Bairamian ◽

Michael E. Newmark ◽

Giovanni DiChiro ◽

Roger J. Porter ◽

...

Keyword(s):

Positron Emission Tomography ◽

Glucose Metabolism ◽

Regions Of Interest ◽

Cerebral Glucose Metabolism ◽

Emission Tomography ◽

Metabolic Rates ◽

Seizure Disorders ◽

Positron Emission ◽

Ictal Activity ◽

Cortical Regions

We used serial positron emission tomography scans with [18F]2-deoxyglucose to study the effect of phenytoin on human cerebral glucose metabolism in 10 patients with seizure disorders. Local CMRglu for each patient was measured in 10 regions of interest. EEGs were performed during each procedure to match scans for state of consciousness and exclude data from scans with ictal activity. Serial scans without a drug change were performed in six control patients. Metabolic rates were significantly lower in two cortical regions while patients were taking phenytoin. No significant changes on repeat scan were seen in the control population. Measured across all regions of interest, metabolic rates were 13% higher when patients were off phenytoin (p < 0.02).

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