1. Department of Veterinary Medicine; Rakuno Gakuen University; Ebetsu; Hokkaido; 069-8501; Japan
2. Department of Veterinary Science; Rakuno Gakuen University; Ebetsu; Hokkaido; 069-8501; Japan
3. Department of Functional Morphology, Laboratory of Histology and Cytology; Hokkaido University Graduate School of Medicine; Sapporo; 060-8638; Japan
4. Laboratory of Pharmacology, Faculty of Applied Biological Science; Gifu University; Gifu; 501-1193; Japan
5. Common Resources Group; Okinawa Institute of Science and Technology; Okinawa; 904-0411; Japan