Tigerstedt and the discovery of renin. An historical note.

R ENIN was discovered at the Karolinska Institute in 1898 by Robert Tigerstedt, a noted physiologist, and Per Bergman, his 24-yearold student.This discovery, a result of model scientific method in action, lay dormant for 40 years before its importance was first appreciated. Once appreciated, the awareness of a renal pressor substance led to thousands of major researches and far-reaching findings that immeasurably advanced medical science, especially in the approach to patients with hypertension. Thus, the discovery of renin ranks as a landmark in the history of medicine, and it is remarkable that the story of this discovery has not been presented heretofore. Robert Adolph Armand Tigerstedt (fig. 1) was born February 28, 1853 in Helsinki, Finland where his father, Karl, was a history professor. Robert's basic education at the University of Helsinki was in the physical and natural sciences, particularly in chemistry because of the influence of his teacher, the famed C. J. Arrhenius. At the University of Helsinki, Tigerstedt studied medicine from 1876-1880, not with the intention of becoming a practitioner, but because of his interest in research in natural science. During this period he maintained an active interest in the basic sciences, particularly physiology. Gustav Retzius was his trusted adviser in medical school, and he later influenced Robert to move to Stockholm. While a medical student, Robert married his cousin Ljuba Martinau, a Ukrainian, and their first child, Maria (1879-1976), was born before his graduation. After completing his medical education, Tigerstedt had hoped to remain in Helsinki in an academic appointment. However, his doctoral dissertation ("On the Mechanical Stimulation of the Nervous System") displeased Hallsten, the professor of physiology at the