1. Kojiro Matsuda (1908-1993): Dr. K. Matsuda devoted his academic life to the development of cardiac electro-physiology/pathophysiology and circulation physiology. He and his group have recorded, for the first time, action potentials in specialized cardiac muscle tissues including atrioventricular node and established physiological basis of impulse conducting system in the heart. (M. Kameyama) 2. Yasuyoshi Nisimaru (1897-1990): Dr. Y. Nisimaru established with his numerous pupils (over 140 members) the concept of body fluid circulation; blood (William Harvey), lymph (Claude Bernard) and tissue fluid are linked and essentially one and the same extracellular fluid. He was a great teacher and encouraged many, even outside his immediate circle, for reasearch. He was one of the members who founded the Physiological Society of Japan in 1922 (Naoko Nisimaru). [J Physiol Sci. 2006;56 Suppl:S7]