1. From the Department of Pharmacology and Toxicology (T.O.P., J. Rysä, H.R., H.L.) and Department of Physiology (J. Ronkainen), Biocenter Oulu, and the Department of Pathology (Y.S.), University of Oulu, Oulu, Finland; and the Department of Cardiovascular Surgery (P.T., J.S., T.J.) and Departments of Anaesthesiology and Surgery (P.O.), Oulu University Hospital, Oulu, Finland.