1. Protein Engineering Research Institute, 6-2-3, Furuedai, Suita 565, Japan
2. International Research Laboratories, CIBA-GEIGY (Japan), 10-66, Miyuki-Cho, Takarazuka 665, Japan
3. National Cardiovascular Center Research Institute, 5-7-1, Fujisiro-dai, Suita 565, Japan