 Bradykinin was to prove a new autopharmacological principle, i.e., a substance that is released in the body by a metabolic modification from precursors, which are pharmacologically active.The discovery of bradykinin led to a new understanding of many physiological and pathological phenomena including circulatory shock induced by venoms and toxins.Ultimately, the extensive study of the origins of its formation in the body, by Sérgio Henrique Ferreira, a noted Brazilian pharmacologist, and others, led to the development of new anti-hypertensive agents in humans, such as captopril, developed by Squibb under the name of Capoten, and still widely used.