Renal physiology of renal artery stenosis. Implications for captopril-stimulated renography.

Captopril-stimulated renography is emerging as a useful diagnostic tool for the evaluation of the hypertensive patient suspected of having renovascular hypertension (RVHT). This overview focuses upon the alterations in renal hemodynamics and function induced by renal artery stenosis (RAS) and reviews the effects of angiotensin-converting enzyme (ACE) inhibition upon blood pressure and kidney function in the various experimental models of RVHT. Understanding the effects of ACE inhibition upon the kidney distal to a stenosis and appreciating the potential effect of sodium balance or antihypertensive medications are crucial in anticipating the putative changes in the radionuclide studies of the renovascular bed following ACE inhibition.