Cellular biology of the renin-angiotensin systems.

The renin-angiotensin system is a major determinant of arterial pressure and intravascular volume in human beings. Recent evidence, however, suggests that renin can be synthesized at local tissue sites and that these local renin-angiotensin systems subserve important physiologic functions. In addition, it appears that there exist intracellular renin-angiotensin "systems" capable of generating angiotensin II intracellularly.