The key difference between vasa recta and peritubular capillaries is that vasa recta are the special type of peritubular capillaries that supply oxygen and nutrients to the medulla of the kidney while peritubular capillaries are the capillaries that arise from the efferent arteriole and feed the kidney with oxygen and nutrients.
The kidney is the organ that filters blood and removes wastes materials from the body via urine. The nephron is the basic functional unit of the kidney. There are two arterioles coming and going from the glomerulus of the nephron. They are afferent arteriole and efferent arteriole. Moreover, an efferent arteriole is divided into a capillary network called peritubular capillaries. In addition, vasa recta are special type of peritubular capillaries that supply nutrients and oxygen to the medulla of the kidney.
CONTENTS
1. Overview and Key Difference
2. What are Vasa Recta
3. What are Peritubular Capillaries
4. Similarities Between Vasa Recta and Peritubular Capillaries
5. Side by Side Comparison – Vasa Recta vs Peritubular Capillaries in Tabular Form
6. Summary
What are Vasa Recta?
Vasa recta are the special type of peritubular capillaries that feed medulla of the kidney with oxygen and nutrients. They specifically arise from the efferent arteriole of juxtamedullary nephrons and wind around their Henle loops. Moreover, they form a parallel set of hairpin loops within the medulla. Vasa recta are highly permeable to solute and water.
Figure 01: Vasa Recta
In addition to supplying nutrients to the medulla of the kidney, vasa recta carry out another function. Vasa recta help in the removal of water and solute added to the medullary interstitium by the nephron.
What are Peritubular Capillaries?
Peritubular capillaries are the capillary network arising from the efferent arteriole coming out from the glomerulus. Peritubular capillaries provide nutrients and oxygen to the renal cortex. Therefore, a larger portion of the peritubular capillaries is in the renal cortex. They surround the proximal and distal tubules.
Figure 02: Peritubular Capillaries
Furthermore, special peritubular capillaries called vasa recta surround the Henle loops of juxtamedullary nephrons. These capillaries facilitate the reabsorption of valuable substances such as glucose, amino acids, ions, minerals and water, etc, back to the blood from the filtrate. Finally, the blood of peritubular capillaries exits the kidney via the renal vein.
What are the Similarities Between Vasa Recta and Peritubular Capillaries?
- Vasa recta are a special type of peritubular capillaries.
- They are present in the kidney.
- Furthermore, they arise from the efferent arteriole.
- Both provide nutrients and oxygen to the kidneys.
- Moreover, they facilitate the reabsorption of useful substances back to the blood from the glomerular filtrate.
What is the Difference Between Vasa Recta and Peritubular Capillaries?
Vasa recta are the tiny capillaries that surround Henle loops and provide nutrients and oxygen to renal medulla while peritubular capillaries are the capillaries that surround the proximal and distal tubules and provide nutrients and oxygen to the renal cortex. Thus, this is the key difference between vasa recta and peritubular capillaries.
Summary – Vasa Recta vs Peritubular Capillaries
Vasa recta are a special type of peritubular capillaries that surround Henle loops of juxtamedullary nephrons while peritubular capillaries are the capillary network arising from the efferent arteriole. This is the key difference between vasa recta and peritubular capillaries. The renal cortex contains a large portion of the peritubular capillaries while renal medulla contains the vasa recta.
Reference:
1. “Vasa Recta.” Vasa Recta – an Overview | ScienceDirect Topics, Available here.
Image Courtesy:
1. “Figure 41 03 03” By CNX OpenStax – (CC BY 4.0) via Commons Wikimedia
2. “Physiology of Nephron” By Madhero88 – Own work (CC BY 3.0) via Commons Wikimedia