Björn Folkow (; 13 October 1921 - 23 July 2012) was a Swedish physiologist. He was professor in physiology at the University of Gothenburg between 1961 and 1987 and a member of the Royal Swedish Academy of Sciences. Biography Björn Folkow was born in Halmstad, Sweden. He studied medicine at Lund University where he continued with doctoral studies in physiology. He defended his thesis on 9 May 1949. Soon thereafter he became associate professor ('laborator') at the new Department of Physiology at the University of Gothenburg. He became full professor in 1961 and remained there until his retirement in 1987. Even after retirement he continued being active in the department until shortly before his death in 2012. Folkow was a member of the Royal Swedish Academy of Sciences and member of the Danish and Russian Academies of Sciences. The European Society of Hypertension established the Björn Folkow Award and Lecture in 1989. Scientific activity Folkow published more than 400 scientific papers, covering most areas of cardiovascular physiology. He was an international authority in the field of high blood pressure. His main contributions arguably are found in the following areas: The myogenic response of blood vessels. In 1902 Bayliss described that many blood vessels respond to an elevation of transmural pressure by constriction, finally reaching a diameter that is smaller than the initial diameter at the lower pressure. This observation, which had not received much attention at the time, was studied by Folkow as part of his thesis work and subsequently for more than a decade. He described this mechanism as an essential element in vascular control. This is now well-established knowledge in cardiovascular physiology. The structural adaptation of blood vessels to elevated blood pressure. Folkow and coworkers studied the blood flow in the forearm in persons with high blood pressure, finding an elevated resistance to flow even in situations when the blood vessels would be fully dilated. This indicated a structural adaptation of the blood vessels to a state with smaller lumen diameter but thicker wall (what now is termed remodelling). This confers to the vessel wall what corresponds to a longer lever, enabling them to contract against higher pressures. This can be seen as the beginning of a vicious circle, where an elevation of pressure causes remodelling that promotes further pressure elevation. Folkow's description of these vascular alterations has since been verified in a large number of studies. The