Renal medulla

Source: Wikipedia, the free encyclopedia.
(Redirected from
Medullary interstitium
)
Renal medulla
Calyx
Details
SystemUrinary system
Identifiers
Latinmedulla renalis
MeSHD007679
TA98A08.1.01.020
TA23369
FMA74268
Anatomical terminology]

The renal medulla (Latin: medulla renis 'marrow of the kidney') is the innermost part of the

collecting duct, leading to the renal pelvis, the dilated portion of the ureter
.

The renal medulla contains the structures of the

vasa rectae (both spuria and vera), the venulae rectae, the medullary capillary plexus, the loop of Henle, and the collecting tubule.[1]
The renal medulla is hypertonic to the filtrate in the nephron and aids in the reabsorption of water.

Blood is filtered in the glomerulus by solute size. Ions such as sodium, chloride, potassium, and calcium are easily filtered, as is glucose. Proteins are not passed through the glomerular filter because of their large size, and do not appear in the filtrate or urine unless a disease process has affected the glomerular capsule or the proximal and distal convoluted tubules of the nephron.

Though the renal medulla only receives a small percentage of the renal blood flow, the oxygen extraction is very high, causing a low oxygen tension and more importantly, a critical sensitivity to hypotension, hypoxia, and blood flow.[2] The renal medulla extracts oxygen at a ratio of ~80% making it exquisitely sensitive to small changes in renal blood flow. The mechanisms of many perioperative renal insults are based on the disruption of adequate blood flow (and therefore oxygen delivery) to the renal medulla.[2]

Interstitium

The medullary interstitium is the tissue surrounding the

inner medullary collecting duct.[3]

Pyramids

Renal pyramids
Renal papilla
  • 17. Renal column
    • Details
    SystemUrinary system
    Identifiers
    Latinpyramides renales
    MeSHD007679
    TA98A08.1.01.020
    TA23369
    FMA74268
    Anatomical terminology]

    Renal pyramids (or malpighian pyramids or Malpighi's pyramids named after

    minor calyx
    , made of parallel bundles of urine collecting tubules.

    Papilla

    The renal papilla is the location where the

    papillary duct
    to channel the fluid. Transitional epithelium begins to be seen.

    Clinical significance

    Some chemicals toxic to the kidney, called

    acetylsalicylic acid, and phenylbutazone, in combination with dehydration. Perturbed renal papillary development has also been shown to be associated with onset of functional obstruction and renal fibrosis.[5][6][7]

    Renal papillary damage has also been associated with nephrolithiasis and can be quantified according to the papillary grading score, which accounts for contour, pitting, plugging and randall plaque.[8]

    Image gallery

    • Renal medulla
      Renal medulla
    • Renal medulla
      Renal medulla
    • Renal papilla
      Renal papilla
    • Frontal section through the kidney
      Frontal section through the kidney
    • Vertical section of kidney. (Label "medullary sub." visible near top.)
      Vertical section of kidney. (Label "medullary sub." visible near top.)
    • Kidney anatomy, with pyramids labeled at right
      Kidney anatomy, with pyramids labeled at right

    See also

    References

    Public domain This article incorporates text in the public domain from page 1221 of the 20th edition of Gray's Anatomy (1918)

    1. ^ Kelly CR, Landman J (March 2012). The Netter Collection of Medical Illustrations: Urinary System. Elsevier Health Sciences. plate 337
    2. ^
      ISBN 978-0-323-79677-4
      .
    3. ISBN 1-4160-2328-3
      . Page 837
    4. ISBN 978-0-7020-4747-3
      .
    5. S2CID 2777257
      .
    6. S2CID 13482413
      .
    7. S2CID 22837861
      .
    8. PMID 27824271
      .

    External links
    Retrieved from "https://en.wikipedia.org/w/index.php?title=Renal_medulla&oldid=1209807575#Interstitium"