[Renin-angiotensin system. Physiological importance. Methods and study in humans (author's transl)]

After a brief review of the biochemistry of the renin-angiotensin system (R. A. S.) components and of their pharmacological inhibitors, the authors describe the main biological effects of angiotensins. A particular emphasis is given to the synergistic effects of the sympathetic nervous system and of the R. A. S., and their major influence on the regulation of hydromineral metabolism and blood pressure. The methods developed for the study of R. A. S. are critically described. Finally, the most important clinical indications of the study of R. A. S. activity are given, and a special attention is paid to the conditions in which such a study must be developed in humans.