Related Experiment Video
Updated: Oct 9, 2026
Assessment of Vascular Function in Patients With Chronic Kidney Disease
Published on: June 16, 2014
Renal artery stenosis detection by combined Gates' technique and captopril test in hypertensive patients
A Cuocolo1, S Esposito, M Volpe
1Istituto di Scienze Radiologiche, Facoltà di Medicina, Università di Napoli, Italy.
Insights
Captopril significantly reduced glomerular filtration rate (GFR) in hypertensive patients with renal artery stenosis (RAS), but not in those with essential hypertension (EH). This radionuclide technique helps identify angiotensin II-dependent renovascular hypertension.
Area of Science:
- Nephrology
- Nuclear Medicine
- Cardiology
Background:
- Hypertension management requires accurate assessment of renal function.
- Renovascular hypertension (RVH) is often secondary to renal artery stenosis (RAS).
- Angiotensin II plays a key role in the pathophysiology of RVH.
Purpose of the Study:
- To investigate the acute effects of captopril on glomerular filtration rate (GFR) in hypertensive patients.
- To differentiate between RAS and essential hypertension (EH) using a radionuclide technique.
- To assess the utility of captopril challenge test in identifying angiotensin II-dependent renal changes.
Main Methods:
- Utilized a radionuclide technique with [99mTc]DTPA and Gates' method to measure total and split GFR.
- Administered oral captopril (50 mg) to 11 hypertensive patients (5 with RAS, 6 with EH).
- Determined GFR under control conditions and after captopril administration.
Main Results:
- Captopril significantly decreased GFR in the stenotic kidneys of RAS patients (p < 0.01) but not in non-stenotic kidneys.
- Total GFR decreased significantly after captopril in RAS patients (p < 0.05).
- No significant GFR changes were observed in EH patients after captopril.
Conclusions:
- Computed radionuclide GFR determination with a captopril test effectively unmasks angiotensin II-dependent renal function.
- This technique is valuable for clinical identification of patients with renovascular hypertension.
- The radionuclide method demonstrated good reproducibility for GFR assessment.
Abstract:
We studied 11 hypertensive patients by a radionuclide technique using Gates' method with [99mTc]DTPA to investigate the acute effects of captopril on glomerular filtration rate (GFR). Five patients had hypertension with unilateral renal artery stenosis (RAS) angiographically documented and six patients had essential hypertension (EH). Total and split GFR were determined under control conditions and after oral administration of captopril (50 mg). In the patients with RAS, captopril induced a significant decrease of GFR in the stenotic kidneys (from 42.4 +/- 4 to 29.6 +/- 3 ml/min, p less than 0.01), while no changes were observed in the nonstenotic kidneys (from 61.2 +/- 3 to 61.6 +/- 5 ml/min, NS). Total GFR was 103.6 +/- 5 ml/min under control conditions and decreased to 91.8 +/- 6 ml/min after captopril (p less than 0.05). No significant changes of GFR were detected after captopril administration in patients with EH. In a separate group of ten patients with EH, good correlation between 24-hr creatinine clearance and fractional uptake of [99mTc]DTPA was obtained. Good reproducibility of this radionuclide technique was also shown. This study demonstrates that the computed radionuclide GFR determination coupled with the captopril test allows one to unmask angiotensin II-dependent renal function and hemodynamic changes. This technique can be useful in clinical practice for identifying patients with renovascular hypertension.
Related Concept Videos
01:30Antihypertensive Drugs: Angiotensin-Converting Enzyme Inhibitors
01:25Antihypertensive Drugs: Direct Renin Inhibitors
01:22Aortic Regurgitation II: Clinical Features and Diagnostic Tests
01:30Hypertension III: Clinical Manifestations and Diagnostic Studies
01:21Peripheral Arterial Disease II: Clinical Manifestations and Diagnostic Evaluation
01:19Imaging Studies VII: Vascular Imaging