RT Journal Article
SR Electronic
T1 Adenosine A<sub>1</sub> Receptor Mapping of the Human Brain by PET with 8-Dicyclopropylmethyl-1-<sup>11</sup>C-Methyl-3-Propylxanthine
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 32
OP 37
VO 46
IS 1
A1 Fukumitsu, Nobuyoshi
A1 Ishii, Kenji
A1 Kimura, Yuichi
A1 Oda, Keiichi
A1 Sasaki, Toru
A1 Mori, Yutaka
A1 Ishiwata, Kiichi
YR 2005
UL http://jnm.snmjournals.org/content/46/1/32.abstract
AB Adenosine is an endogenous modulator of synaptic functions in the central nervous system. To investigate the physiologic and pathologic roles of the adenosine receptors in the human brain, PET is a powerful in vivo technique. In this study, we quantitatively evaluated the distribution of a major subtype A1 adenosine receptor in the human brain by PET with a newly developed radioligand, 8-dicyclopropylmethyl-1-11C-methyl-3-propylxanthine (11C-MPDX). Methods: In 5 healthy volunteers, after PET measurement of the regional cerebral blood flow (rCBF) with 15O-H2O, a 60-min PET scan with 11C-MPDX was performed. The distribution volume (DV) of 11C-MPDX was quantitatively evaluated by Logan’s graphical analysis. Results: 11C-MPDX was taken up at a high level, reaching a peak at 2–2.5 min, followed by a rapid decrease. The unchanged form of 11C-MPDX in plasma was 75% at 60 min after injection. The DV of 11C-MPDX was large in the striatum and thalamus, moderate in the cerebral cortices and pons, and small in the cerebellum. The distribution pattern of 11C-MPDX in the brain was coincident with that of adenosine A1 receptors in vitro, reported previously, but discretely different from that of rCBF. Conclusion: 11C-MPDX PET has the potential for mapping adenosine A1 receptors in the human brain.