RT Journal Article SR Electronic T1 Imaging Neuroinflammation in Alzheimer's Disease with Radiolabeled Arachidonic Acid and PET JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1414 OP 1421 DO 10.2967/jnumed.107.049619 VO 49 IS 9 A1 Giuseppe Esposito A1 Giampiero Giovacchini A1 Jeih-San Liow A1 Abesh K. Bhattacharjee A1 Dede Greenstein A1 Mark Schapiro A1 Mark Hallett A1 Peter Herscovitch A1 William C. Eckelman A1 Richard E. Carson A1 Stanley I. Rapoport YR 2008 UL http://jnm.snmjournals.org/content/49/9/1414.abstract AB Incorporation coefficients (K*) of arachidonic acid (AA) in the brain are increased in a rat model of neuroinflammation, as are other markers of AA metabolism. Data also indicate that neuroinflammation contributes to Alzheimer's disease (AD). On the basis of these observations, K* for AA was hypothesized to be elevated in patients with AD. Methods: A total of 8 patients with AD with an average (±SD) Mini-Mental State Examination score of 14.7 ± 8.4 (mean age, 71.7 ± 11.2 y) and 9 controls with a normal Mini-Mental State Examination score (mean age, 68.7 ± 5.6 y) were studied. Each subject received a 15O-water PET scan of regional cerebral blood flow, followed after 15 min by a 1-11C-AA scan of regional K* for AA. Results: In the patients with AD, compared with control subjects, global gray matter K* for AA (corrected or uncorrected for the partial-volume error [PVE]) was significantly elevated, whereas only PVE-uncorrected global cerebral blood flow was reduced significantly (P < 0.05). A false-discovery-rate procedure indicated that PVE-corrected K* for AA was increased in 78 of 90 identified hemispheric gray matter regions. PVE-corrected regional cerebral blood flow, although decreased in 12 regions at P < 0.01 by an unpaired t test, did not survive the false-discovery-rate procedure. The surviving K* increments were widespread in the neocortex but were absent in caudate, pallidum, and thalamic regions. Conclusion: These preliminary results show that K* for AA is widely elevated in the AD brain, particularly in regions reported to have high densities of senile (neuritic) plaques with activated microglia. To the extent that the elevations represent upregulated AA metabolism associated with neuroinflammation, PET with 1-11C-AA could be used to examine neuroinflammation in patients with AD and other brain diseases.