ALTHOUGH the names of Tigerstedt and Bergman1 are associated with the first description in 1898 of renin extracted from the kidney, it may come as a surprise that when Tigerstedt, who was the senior worker in the partnership and the Professor of Physiology in the Karolinska Institute, Stockholm, died, there was no mention of renin in the various reviews of his life's work. He would probably have been equally surprised to see the vast new field of renal, adrenal and cardiovascular physiology that this discovery opened up.2 , 3 Renin and Renin-like Enzymes Renin should refer purely to the enzyme extracted . . .