Renal Artery StenosisMedical Author:
Benjamin Wedro, MD, FACEP, FAAEM
Benjamin Wedro, MD, FACEP, FAAEMDr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center. Medical Editor:
Melissa Conrad Stöppler, MD, Chief Medical Editor
Melissa Conrad Stöppler, MD, Chief Medical EditorMelissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Renal Artery Stenosis OverviewAside from filtering blood and making urine, the kidneys have other functions. One such function is monitoring blood pressure (performed by special cells called macula densa). Using a chemical messenger called angiotensin, these cells can help adjust blood flow throughout the body and maintain normal blood pressure. The angiotensin acts by increasing muscle tone in small artery walls to help boost blood pressure. Angiotensin also stimulates the release of aldosterone, which helps the body retain sodium and water, increasing the amount of fluid within the blood vessels. Most people with high blood pressure have essential hypertension (hyper=more + tension=pressure), meaning that the cause of the high blood pressure is unknown. However, one known cause of hypertension is renal artery stenosis (renal=kidney + stenosis=narrowing). Each kidney gets its blood flow via a renal artery that arises from the aorta, the major blood vessel from the heart. If one of the renal arteries narrows, it may cause decreased blood flow to the kidney and to the macula densa (the specialized, blood-pressure sensing cells in the kidney). These cells falsely presume that this low blood flow is being experienced by the rest of the body and that overall blood pressure is too low. They respond by increasing secretion of angiotensin, triggering the body's response to increase blood pressure. Must Read Articles Related to Renal Artery Stenosis
Acute Kidney Failure
Kidney failure, or the ability of the kidneys to filter water and waste is caused by prerenal, postrenal, or renal problems with the kidney(s). Symptoms of kidn...learn more >>
Chronic Kidney Disease
Twenty percent of people over the age of 20 years will develop chronic kidney disease in their lifetime. Chronic kidney disease causes are diseases of the kidne...learn more >>
Dehydration in Adults
Dehydration occurs when the loss of body fluids (mostly water), exceeds the amount that is taken in. Causes of dehydration include fever, vomiting, diarrhea, di...learn more >>
|
Hypertension
Get tips on handling your hypertension.
From WebMD
Heart Health Resources
Featured Centers
Health Solutions From Our Sponsors
Read What Your Physician is Reading on Medscape
Renal Artery Stenosis »
Specialists have known for a long time that renal artery stenosis (RAS) is the major cause of renovascular hypertension and that it may account for 1-10% of the 50 million people in the United States who have hypertension.
Featured Topics
Medical Dictionary
Pill Identifier on RxList
- quick, easy,
pill identification
Find a Local Pharmacy
- including 24 hour, pharmacies



