Angiotensin converting enzyme: history and relevance

The renin angiotensin system (RAS) is now recognized as the body's most powerful hormone system for controlling renal hemodynamics and sodium excretion and, therefore, body fluid volumes and arterial pressure. The discovery of angiotensin converting enzyme inhibitors (ACEi) was a keystone for the understanding of the significance of the RAS since ACEi proved to be effective in controlling hypertension and heart failure and in preventing the development of the vascular injury of chronic diseases like scleroderma and diabetes mellitus. The success of ACEi stimulated the research into inhibitors of other actors of the RAS like renin or angiotensin receptor antagonists. It is not often realized that the discovery of ACEi owes a great deal to basic research in which the venom of a Brazilian viper, Bothrops Jararaca, was instrumental for the discovery of bradykinin by Rocha e Silva and the bradykinin potentiating factor. This article reviews the contribution of the converting enzyme inhibitors for the demonstration of the relevance of the RAS to several human pathologies.