1. Department of Endocrinology, Metabolism and Nephrology, Kochi Medical School, Kochi University, Kohasu, Oko-Cho, Nankoku, Kochi 783-8505, Japan
2. Laboratory of Anatomy, Department of Basic Veterinary Sciences, Hokkaido University, Kita 18, Nishi 9, Kita-Ku, Sapporo 060-0818, Japan