Differential actions of angiotensin-(1-7) in the kidney

Angiotensin-(1-7) is a bioactive component of the renin-angiotensin system that is endogenously formed in the circulation and various tissues by several enzymatic pathways from either angiotensin (Ang) I or Ang II. Initial studies indicated that Ang-(1-7) mimicked some of the effects of Ang II, including stimulation of release of prostanoids and vasopressin. However, Ang-(1-7) is devoid of the vasoconstrictor, central presser, or thirst-stimulating actions associated with Ang II. In fact, new findings reveal depressor, vasodilator, and antihypertensive actions that may be more apparent in hypertensive animals or humans. Thus, increasing evidence suggests that Ang-(1-7) may oppose the actions of Ang II directly or as a result of increasing prostaglandins or nitric oxide. In this review, we examine recent studies to address whether the kidney is a target organ for antihypertensive actions of Ang-(1-7).