1. Zentrum Physiologie, Abt. Vegetative PhysiologieMedizinische Hochschule HannoverHannoverGermany
2. Department of MedicineThe Johns Hopkins UniversityBaltimoreMarylandUSA
3. Physiologisches Institut der Universität ZürichWinterthurerstr. 190CH‐8057ZürichSwitzerland
4. Department of Biomedical ScienceAlfred Denny Building, University of Sheffield, Western BankSheffieldSouth YorkshireS10 2TNUK
5. Department of Cellular and Molecular PhysiologyYale School of MedicineNew HavenConnecticutUSA
6. Dipartimento di Chimica, Laboratorio di Chimica BioinorganicaUniversity of FlorenceSesto FiorentinoFirenzeItaly