How a Brazilian pit viper's venom led to a blood pressure drug

In 1965, Brazilian pharmacologist Sergio Ferreira described a substance in the venom of the jararaca pit viper that enhanced bradykinin, a natural peptide that widens blood vessels and lowers blood pressure. The discovery opened a path to a new class of heart medicines and contributed to captopril, an oral drug approved in the United States in 1981 for hypertension.