ACE in three tunicae of rat aorta: expression in smooth muscle and effect of renovascular hypertension

Gelas. ACE in three tunicae of rat aorta: expression in smooth muscle and effect of renovascular hypertension. Am. J. PhysioZ. 267 (Heart Circ. PhysioZ. 36): H1777-H1784, 1994.-Angiotensin I-converting enzyme (ACE) is known to be pres-ent at the surface of endothelial cells and also in the adventi-tia in large vessels. The presence of ACE in the vascular smooth muscle remains controversial. We microdissected seg-ments of adventitia and media with or without endothelium from a region devoid of collateral arteries. The membrane-bound ACE activity in the media averaged 41 % (pmol lglycine- l- 14CJ hippuryl-L-histidyl+leucine hydrolyzed. g tissue- l. min- l) of the values found in the whole aorta, whereas the adventitia contained only 6%. Immunoreactive ACE in media was characterized by Western blotting. ACE mRNAs were detected and characterized after polymeras