1. Department of Physiology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu 807‐8555, Japan
2. Department of Foods and Human Nutrition, Faculty of Human Life Sciences, Notre Dame Seishin University, Okayama 700‐8516, Japan
3. Department of Pharmacology, University of Occupational and Environmental Health, School of Medicine, Kitakyushu 807‐8555, Japan