Open AccessBiological characters of [ 18 F] O ‐FEt–PIB in a rat model of Alzheimer's disease using micro‐PET imaging 1
Author(s) -
ZHENG Mingqiang,
YIN Duanzhi,
ZHANG Lan,
LEI Bei,
CHENG Dengfeng,
CAI Hancheng,
HAN Yanjiang,
WU Mingxing,
ZHANG Hong,
WANG Jing
Publication year - 2008
Publication title -
acta pharmacologica sinica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.514
H-Index - 90
eISSN - 1745-7254
pISSN - 1671-4083
DOI - 10.1111/j.1745-7254.2008.00785.x
Subject(s) - disease , alzheimer's disease , pet imaging , positron emission tomography , medicine , nuclear medicine , pathology
Aim: To evaluate whether the newly‐synthesized positron emission tomography (PET) tracer, [ 18 F]2‐(4′‐(methylamino)phenyl)‐6‐fluoroethoxy‐ benzothiazole ([ 18 F] O ‐FEt‐PIB), could bind to β‐amyloid aggregates in a rat model of Alzheimer's disease (AD) using micro‐PET. Method: [ 18 F] O ‐FEt‐PIB was synthesized and purified by radio HPLC. PET imaging was performed with a R4 rodent model scanner in 3 model and 3 control rats. Dynamic PET scans were performed for 40 min in each rat following an injection of approximately 37 MBq of [ 18 F] O ‐FEt‐PIB. Static scans were also performed for 15 min in each rat. PET data were reconstructed by a maximum posteriori probability algorithm. On the coronal PET images, regions of interest were respectively placed on the cortex, hemicerebrum [including the hippocampus and thalamus (HT)], and were guided by a 3‐D digital map of the rat brain or the brain images of [ 18 F]2‐Deoxy‐2‐fluoro‐J D ‐glucose ([ 18 F]FDG) in normal rats. Time‐activity curves (TAC) were obtained for the cerebrum and cerebellum. The activity difference value (ADV) between 2 hemicerebrums was also calculated. Results: The TAC for [ 18 F] O ‐FEt‐PIB in the cerebrum or cerebellum peaked early (at approximately 2 min), but washed out a little slowly. In the dynamic and static micro‐PET images, increased radioactivity was found in the area of the right HT in the model rats where infused with β‐amyloid (1–40). No distinct difference of radioactivity was found between the right and left HT areas in the control rats. The ADV( HT ) was approximately 14.6% in the AD model rats and approximately 4 times greater than that of the control rats (3.9%). Conclusion: To our knowledge, this study is the first to evaluate a small molecular PET probe for the p‐amyloid deposits in vivo using micro‐PET imaging in an AD‐injected rat model. The suitable biological characters showed that the tracer had potential to be developed as a probe for detecting β‐amyloid plaques in AD.