Targeting tissue angiotensin-converting enzyme for imaging cardiopulmonary fibrosis.

Convincing clinical and experimental evidence exists that the renin-angiotensin system and its primary effector peptide, angiotensin II, are linked to the pathophysiology of interstitial fibrosis in the heart and in the lung. Tissue angiotensin-converting enzyme and locally synthesized angiotensin II exert local trophic effects, which regulate fibroblast growth and proliferation. Thus, the presence of tissue renin-angiotensin system offers an opportunity for targeted imaging, which may be valuable for understanding the pathobiology of cardiopulmonary disorders and for guiding medical therapy.