Hi Desiree,
This is actually quite a complicated mechanism of action.
ACE inhibitor have the potential to both protect and hurt the kidney. Generally, if the kidney is healthy it will be protective and if the kidney is not quite functioning properly it may become damaging.
ACE inhibitor modulate blood flow through the kidney. In doing this it changes pressures that the smallest blood vessels experience. This may be good or bad.
The issue of use in a transplant patient is even more complex because of the various medications. My best advice for you is to talk with your nephrologist about this. If your nephrologist recommends it it should be safe for you. If you are taking one, regular follow up with your doctor is important to make sure that everything continues to go well.
Best wishes.
