Effect of zinc depletion on angiotensin I-converting enzyme in arterial walls and plasma of the rat.

The effect of zinc depletion and of additional angiotensin I-converting enzyme (ACE) inhibitor treatment was studied on ACE in aortic and other tissues, in plasma and on systolic blood pressure of the rat. Zinc deprivation significantly reduced plasma zinc concentration, plasma and testicular ACE activities and blood pressure, but stimulated aortic ACE while lung values remained constant. Zinc deficiency combined with ACE inhibition further suppressed plasma ACE and stimulated the aortic enzyme earlier. Zinc repletion experiments (in vitro) suggest the existence of a feedback mechanism controlling ACE synthesis depending on plasma ACE activity.