KIDNEYS

FUNCTIONS

Capsules of Kidney

Formation of urine

  1. Fibrous Capsule
  1. Perirenal/Perinephric Fat

Removes nitrogenous waste product of protein metabolism

  1. Renal Fascia

Maintain electrolyte and water balance

  1. Pararenal/Paranephric Fat

Secrete Renin

Thin, closely envelopes the kidney

Adipose tissue layer

Fibroareolar sheath

Cushion, varying amounts of fat

Produce erythropoietin

Produce 1' 25' hydroxy cholecalciferol

innermost

outermost

regulates blood flow and BP

for maturation of RBC

Control calcium metabolism

LOCATION

divided into

Retroperitoneal organ

Either side of vertebral column

Anterior layer
-Fascia of Gerota

Occupies

Posterior layer
-Fascia of Zuckerkandall

hypochondrium, epigastrium, lumbar, umbilical

Blood Supply

EXTENT

12th thoracic Vertebra to 3rd lumbar vertebra

Abd. Aorta at L2

Renal a.

5 segmental a.

each segmental a. further:

Lobar a.

Interlobar a.

Arcuate a.

Interlobular artery

Afferent arteriole

AXIS

Glomerulus

Efferent arteriole

Peritubular plexus

Interlobular v.

Long axis

Transverse axis

Arcuate v.

directed downwards and laterally

Interlobar v.

Lobar v.

Segmental v.

directed laterally and backwards

5 segmental veins

Renal v.

Inferior Vena Cava

Structure

outer
Renal substance

MEASUREMENTS

Inner medulla

inner
Renal sinus

Outer cortex

length 11cm

Renal columns

Renal pyramids (about 10)

space that extends into kidney from hilum

contains

Br. of renal a.

Trib. of renal v.

breadth 6cm

thickness 3cm

Renal pelvis

weight

2 to 3 major calyces

7 to 13 minor calyces

male 150gm
female 135gm

expands, indented by 1 to 3 renal papillae

forms a
lobe of Kidney

Renal arches/lobules

to do:
1.External features

  1. Clinical
    3. Structure of uriniferous tubule
    4. Relations
    5. Lymph
    6. Nerve
    7. Vascular segments

Nerve Supply

by Renal plexus

from coeliac plexus

Preganglionic
Sympathetic fibers
T10 - L1

mainly vasomotor

afferent nerves

from
T10 to T12

EXTERNAL FEATURES

Upper Pole/ Upper End

rounded and thicker, Opp. to T12

Lower Pole/ Lower End

directed downwards and laterally, Opp. to L3

Lateral Border

convex and thin

Medial Border

convex in upper and lower part

presents concave hilum in middle

lies 5cm from midline

structures passing- renal v, renal art., renal pelvis (from ant. to post.)

Medullary rays

other strc. - nerves lymphatics and perinephric fat

Collecting tubules radiate from renal pyramid into cortex forming striated conical masses called medullary rays

Surfaces

Posterior surface

Anterior surface

directed backward and medially

contains

collecting tubules

commencement of duct of bellini

  • upper part- diaphragm
    costodiaphragmatic surface
    lf side- 11th&12th rib
    rt side- 12th rib

conical mass

RELATIONS

lower part- psoas maj, quadratus lum, rectus abd(med to lat); subcostal nervs, L1 nerves (above to down)

directed forward & laterally

Vascular Segments

RELATIONS

pass thru cortical arches

RT Kidney- suprarenal, hepatic, duodenal, colic, jejunal areas

LT Kidney- suprarenal, gastric, colic, splenic, pancreatic, jejunal areas

based on distribution of Renal artery in the kidney

no anastomosis between segments and across brodel line

LYMPHATICS

Brodel's line

avascular plane between areas supplied by the anterior and posterior branches of renal artery

Lat. Aortic lymph nodes

line of incision in exploration of kidney during surgery for minimal blood loss
-also for nephrolithotomy (removal of stone)

URINIFEROUS TUBULE

Anterior branch

  1. Apical
  2. Upper
  3. Middle
  4. Lower

Excretory Part

Collecting Part

nephron

Posterior branch

  1. Posterior

Renal corpuscles

renal tubules

collecting tubules

juxtaglomerular apparatus

  1. macula densa
  1. juxtaglomerular cells (JG Cells)
  1. extra glomerular mesenglial cells (Lacis cells)

but not strictly avascular as-
tributaries of renal vein intercommunicate across the line

CLINICAL