Renin activity measurement in the plasma of patients with renovascular hypertension

In our work, we compare measured renin activity in the plasma during the application of captopril test, and renin activity measured in the blood samples, taken during the renal angiography. Renal artery stenosis suspicion existed in all patients. It is well-known that renovascular hypertension evolves, due to the stenosis of renal artery or a bigger branch of hers, which leads to the decrease of renal perfusion and the increase in tubular resorption, along with the activation of renin-angiotensin-aldosterone system. Renal angiography and separated rennin concentration determination is a reliable method of diagnosing. Due to its invasive character, this method is not widely used. It is used with a specific purpose, on patients with increased level of renin activity in plasma, or increased values of rennin concentration in the captopril test. The diagnostical value of captopril test comes from the significant increase of rennin and aldosterone in the plasma, after the administration of captopril. 40 patients who underwent renal angiography in the period from 1995 to 2005, were included in the study. Captopril test was previously done on all of the patients. Renin values in captopril test match the separated renin values measured in blood samples, taken during the renal angiography in 35 patients. Renin activity in the plasma was measured by “ Sorin Biomedica” commercial radioimmunity set (RIA). We can conclude that commercial sets we use for measurement of renin activity in plasma are sensitive and specific, and that the determination of renin activity in plasma, during the captopril test, is a reliable screening method in patients with renvascular hypertension.