@article{oai:repo.qst.go.jp:00045711,
 author = {Miyoshi, Michie and Ito, Hiroshi and Arakawa, Ryosuke and Takahashi, Hidehiko and Takano, Harumasa and Higuchi, Makoto and Okumura, Masaki and Otsuka, Tatsui and Kodaka, Fumitoshi and Sekine, Mizuho and Sasaki, Takeshi and Fujie, Saori and Seki, Chie and Maeda, Jun and Nakao, Ryuji and Zhang, Ming-Rong and Fukumura, Toshimitsu and Suhara, Tetsuya and et.al and 三好 美智恵 and 伊藤 浩 and 荒川 亮介 and 高橋 英彦 and 高野 晴成 and 樋口 真人 and 奥村 正紀 and 大塚 達以 and 小高 文聰 and 関根 瑞保 and 佐々木 健至 and 藤江 沙織 and 関 千江 and 前田 純 and 中尾 隆士 and 張 明栄 and 福村 利光 and 須原 哲也},
 issue = {7},
 journal = {Journal of Nuclear Medicine},
 month = {Jun},
 note = {Peripheral benzodiazepine receptor (PBR) is upregulated in activated glial cells and is therefore a useful biomarker for inflammation in the brain and neurodegenerative disorders. We developed a new PET radioligand, (11)C-AC-N-benzyl-N-ethyl-2-(7-methyl-8-oxo-2-pheyl-7,8-dihydro-9H-purin-9-yl)acetamide ((11)C-AC-5216), that allows the imaging and quantification of PBRs in monkey and mouse brains. The aim of this study was to evaluate a quantification method of (11)C-AC-5216 binding in the human brain. METHODS: A 90-min dynamic PET scan was obtained for each of 12 healthy men after an intravenous injection of (11)C-AC-5216. Regions of interest were drawn on several brain regions. Binding potential, compared with nondisplaceable uptake (BPND), was calculated by a nonlinear least-squares fitting (NLS) method with the 2-tissue-compartment model, and total volume of distribution (VT) was estimated by NLS and graphical analysis methods. RESULTS: BPND was highest in the thalamus (4.6 +/- 1.0) and lowest in the striatum (3.5 +/- 0.7). VT obtained by NLS or graphical analysis showed regional distribution similar to BPND. However, there was no correlation between BPND and VT because of the interindividual variation of K1/k2. BPND obtained with data from a scan time of 60 min was in good agreement with that from a scan time of 90 min (r = 0.87). CONCLUSION: Regional distribution of (11)C-AC-5216 was in good agreement with previous PET studies of PBRs in the human brain. BPND is more appropriate for estimating (11)C-AC-5216 binding than is VT because of the interindividual variation of K1/k2. (11)C-AC-5216 is a promising PET ligand for quantifying PBR in the human brain.},
 pages = {1095--1101},
 title = {Quantitative Analysis of Peripheral Benzodiazepine Receptor in the Human Brain Using PET with 11C-AC-5216},
 volume = {50},
 year = {2009}
}