1. Department of Physiology, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul 120-752, Korea.
2. Department of Anesthesiology and Pain Medicine and Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul 120-752, Korea.
3. Acupuncture and Meridian Science Research Center, Kyung Hee University, Seoul 130-701, Korea.