1. Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, and Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Kyoto University, Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Central Research Laboratories, Miyazaki Medical College, 5200 Kihara, Kiyotake-cho, Miyazaki-gun 889-1601, and Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-Honmachi, Kumamoto 862-0973, Japan