Significance of the Renin-Angiotensin System in Clinical Conditions

The renin-angiotensin system, in both its circulating and local tissue roles, is intertwined with multiple other regulatory and signalling mechanisms in various tissues and organ systems. It plays a central role in the normal regulation of arterial blood pressure and in the development of hypertension, which is an immense global public health burden and a crucial modifiable risk factor in the development of cardiovascular diseases. The renin-angiotensin system plays also important roles in a range of other clinical conditions such as heart failure, kidney failure, diabetes mellitus and others. Therapeutic interventions within the renin-angiotensin system include the use of medications such as angiotensin-converting enzyme inhibitors and angiotensin receptor antagonists, which are well established and have been invaluable as clinically effective tools during many years of practical use. Additionally, numerous other therapeutic approaches targeting components of the renin-angiotensin system have been developed or are currently in development. This chapter will discuss details of the roles of this system in the most relevant clinical conditions.