Angiotensin-sympathetic system interactions in cardiovascular and metabolic disease

BACKGROUND: Blood pressure, as well as blood volume homeostasis, depends to a large extent on humoral influences stemming from the renin-angiotensin axis and the sympathetic nervous system. Evidence has been provided that a large part of this homeostatic modulation is effected by the complex interactions between the two systems. OBJECTIVES: The present review will focus on three major issues. First it will examine the physiological and pathophysiological relevance of angiotensin-sympathetic crosstalk discussing possible sites, mechanisms and effects of the interaction. It will then address the clinical relevance of these inter-relationships by reviewing data collected in cardiovascular and non-cardiovascular diseases. Finally, the influences of angiotensin II on adrenergic function will be examined as possible targets of cardiovascular drug treatment. CONCLUSIONS: By interrupting the influences of angiotensin II on sympathetic function, therapeutic interventions aimed at blocking the renin-angiotensin system exert favourable effects on the haemodynamic, metabolic and renal profile. This has important implications for the treatment of hypertension, congestive heart failure, renal insufficiency and metabolic syndrome.