1. Laboratory of Veterinary Pharmacology, Division of Veterinary Science, Osaka Prefecture University Graduate School of Life and Environmental Science, 1-58 Rinku-ohraikita, Izumisano, Osaka 598-8531, Japan
2. Department of Pharmacology, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan