renal artery

Examples of renal artery in the following topics:

• Supply of Blood and Nerves to the Kidneys

  • The renal veins drain the kidney and the renal arteries supply blood to the kidney.
  • The arterial supply of the kidneys is variable from person to person, and there may be one or more renal arteries supplying each kidney.
  • Due to the position of the aorta, the inferior vena cava, and the kidneys in the body, the right renal artery is normally longer than the left renal artery.
  • The renal arteries carry a large portion of the total blood flow to the kidneys—up to a third of the total cardiac output can pass through the renal arteries to be filtered by the kidneys.
  • The renal arteries split into several segmental arteries upon entering the kidneys, which then split into several arterioles.

• Kidney Structure

  • The arteries, veins, and nerves that supply the kidney enter and exit at the renal hilum.
  • Renal blood supply starts with the branching of the aorta into the renal arteries (which are each named based on the region of the kidney they pass through) and ends with the exiting of the renal veins to join the inferior vena cava.
  • The renal arteries split into several segmental arteries upon entering the kidneys.
  • Each segmental artery splits further into several interlobar arteries that enter the renal columns, which supply the renal lobes.
  • The interlobar arteries split at the junction of the renal cortex and medulla to form the arcuate arteries.

• Internal Anatomy of the Kidneys

  • The renal cortex is a space between the medulla and the outer capsule.
  • The kidneys are surrounded by a renal cortex, a layer of tissue that is also covered by renal fascia (connective tissue) and the renal capsule.
  • The cortex provides a space for arterioles and venules from the renal artery and vein, as well as the glomerular capillaries, to perfuse the nephrons of the kidney.
  • It surrounds a tuft of capillaries called the glomerulus that carries blood from the renal arteries into the nephron, where plasma is filtered through the capsule.
  • The renal pelvis contains the hilium.

• Location and External Anatomy of the Kidneys

  • The kidneys are the primary functional organ of the renal system.
  • They are covered by the renal capsule, which is a tough capsule of fibrous connective tissue.
  • Resting on top of each kidney is an adrenal gland (adrenal meaning on top of renal), which are involved in some renal system processes despite being a primarily endocrine organ.
  • The renal artery branches off from the lower part of the aorta and provides the blood supply to the kidneys.
  • Renal veins take blood away from the kidneys into the inferior vena cava.

• Nephron: The Functional Unit of the Kidney

  • Eighty-five percent of nephrons are cortical nephrons, deep in the renal cortex; the remaining 15 percent are juxtamedullary nephrons, which lie in the renal cortex close to the renal medulla.
  • A nephron consists of three parts: a renal corpuscle, a renal tubule, and the associated capillary network, which originates from the cortical radiate arteries.
  • The renal tubule is a long, convoluted structure that emerges from the glomerulus.
  • The third part of the renal tubule is called the distal convoluted tubule (DCT); this part is also restricted to the renal cortex.
  • Urine leaves the medullary collecting ducts through the renal papillae, emptying into the renal calyces, the renal pelvis, and finally into the bladder via the ureter.

• Overview of the Urinary System

  • The renal system organs include the kidneys, ureters, bladder, and urethra.
  • The  renal system has many functions.
  • The kidneys have an extensive blood supply from the renal arteries that leave the kidneys via the renal vein.
  • The nephrons are made up of a capsule capillaries (the glomerulus) and a small renal tube.
  • Urine passes from the renal tube through tubes called ureters and into the bladder.

• Development of the Heart

  • Approximately 30 posterolateral branches arise from the aorta to form the intercostal arteries, upper and lower extremity arteries, lumbar arteries, and lateral sacral arteries.
  • The lateral branches of the aorta form the definitive renal, suprarenal, and gonadal arteries.
  • The ventral branches of the aorta consist of the vitelline arteries and umbilical arteries.
  • The vitelline arteries form the celiac, superior, and inferior mesenteric arteries of the gastrointestinal tract.
  • After birth, the umbilical arteries form the internal iliac arteries.

• Great Vessels of the Heart

  • Along the way up the body from the iliac veins, the renal and suprarenal veins (kidney and adrenal glands), lumbar veins (from the back), and hepatic veins (from the liver) all drain into the inferior vena cava.
  • The aorta is the largest of the arteries in systemic circulation.
  • The arch of aorta is the peak of the aorta, which breaks off into the left carotid artery, brachiocephalic trunk, and the left subclavian artery.
  • The abdominal aorta is the part of the descending aorta below the diaphragm, which divides into the iliac arteries and branches into the renal and suprarenal arteries.
  • These are the only arteries that carry deoxygenated blood, and are considered arteries because they carry blood away from the heart.

• Arteries, Veins, and Capillaries

  • Arteries take blood away from the heart.
  • The main artery is the aorta that branches into other major arteries, which take blood to different limbs and organs.
  • These major arteries include the carotid artery, which takes blood to the brain; the brachial arteries, which take blood to the arms; and the thoracic artery, which takes blood to the thorax and then into the hepatic, renal, and gastric arteries for the liver, kidneys, and stomach, respectively.
  • The iliac artery takes blood to the lower limbs.
  • The major arteries diverge into minor arteries, and then into smaller vessels called arterioles, to reach more deeply into the muscles and organs of the body.

• Development of the Cardiovascular System

  • On the obliteration of the stapedial artery, this anastomosis enlarges and forms the internal maxillary artery; the branches of the stapedial artery are now branches of this vessel.
  • Approximately 30 posterolateral branches arise off the aorta and will form the intercostal arteries, upper and lower extremity arteries, lumbar arteries, and the lateral sacral arteries.
  • The lateral branches of the aorta form the definitive renal, suprarenal, and gonadal arteries.
  • Finally, the ventral branches of the aorta consist of the vitelline arteries and umbilical arteries.
  • After birth, the umbilical arteries will form the internal iliac arteries.