Propofol anesthesia does not alter regional rates of cerebral protein synthesis measured with L-[1-(11)C]leucine and PET in healthy male subjects.
We report regional rates of cerebral protein synthesis (rCPS) in 10 healthy young males, each studied under two conditions: awake and anesthetized with propofol. We used the quantitative L-[1-(11)C]leucine positron emission tomography (PET) method to measure rCPS. The method accounts for the fraction (lambda) of unlabeled leucine in the precursor pool for protein synthesis that is derived from arterial plasma; the remainder comes from proteolysis of tissue proteins. Across 18 regions and whole brain, mean differences in rCPS between studies ranged from -5% to 5% and were within the variability of rCPS in awake studies (coefficient of variation range: 7% to 14%). Similarly, differences in lambda (range: 1% to 4%) were typically within the variability of lambda (coefficient of variation range: 3% to 6%). Intersubject variances and patterns of regional variation were also similar under both conditions. In propofol-anesthetized subjects, rCPS varied regionally from 0.98+/-0.12 to 2.39+/-0.23 nmol g(-1) min(-1) in the corona radiata and in the cerebellum, respectively. Our data indicate that the values, variances, and patterns of regional variation in rCPS and lambda measured by the L-[1-(11)C]leucine PET method are not significantly altered by anesthesia with propofol.
Bishu
Shrinivas
S
Section on Neuroadaptation and Protein Metabolism, National Institute of Mental Health, Bethesda, Maryland 20892-1298, USA. bishus@mail.nih.gov
Schmidt
Kathleen C
KC
Burlin
Thomas V
TV
Channing
Michael A
MA
Horowitz
Lisa
L
Huang
Tianjiang
T
Liu
Zhong-hua
ZH
Qin
Mei
M
Vuong
B-K
BK
Unterman
Aaron J
AJ
Xia
Zengyan
Z
Zametkin
Alan
A
Herscovitch
Peter
P
Quezado
Zenaide
Z
Smith
Carolyn B
CB
D000328:Adult; D000771:Anesthesia, Intravenous / Q000009:adverse effects; D018686:Anesthetics, Intravenous / Q000009:adverse effects*; D002250:Carbon Radioisotopes; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000378:metabolism; D003071:Cognition / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D007930:Leucine / Q000008:administration & dosage / Q000097:blood; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000187:drug effects; D049268:Positron-Emission Tomography / Q000379:methods; D015742:Propofol / Q000009:adverse effects*; D011446:Prospective Studies; D014176:Protein Biosynthesis / Q000187:drug effects*; D055815:Young Adult
D018686:Anesthetics, Intravenous; D002250:Carbon Radioisotopes; D007930:Leucine; D015742:Propofol