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Development of Venous System

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Development of Venous System Powered By Docstoc
					         OBJECTIVES
• Enumerate the Veins of Embryo
• Discuss the Venous Circulation in Embryo
• Describe Development and Fate of Umbilical
  Veins
• Describe Development and Fate of Vitelline
  Veins
• Describe Development and Fate of Cardinal
  Veins
              Veins of Embryo
Three Pairs of
 Veins are present
 in embryo:
                     Left Horn of
                     Sinus Venosus
Common
 Cardinal Veins
Umbilical
 veins
Vitelline veins
     Venous Circulation of Embryo
Common Cardinal Veins
  collect the deoxygenated
  blood from the body wall.
  Each common cardinal
  vein consists of Anterior
  and posterior common
  cardinal vein
Umbilical Veins carrying the
  oxygenated blood from the
  Placenta
Vitelline veins bring the
  deoxygenated blood from
  the Yolk Sac & gut
                    Umbilical Veins
During the early development of
  embryo, there are two umbilical
  veins right and left. The
  umbilical veins bring the
  nutrient- and oxygen-rich blood
  from the placental villi via the
  umbilical cord to the embryo.
  On later stages of development
  Right umbilical vein degenerate
  and atrophies while the left
  umbilical vein persist through
  out fetal life and degenerate
  after the birth of baby. Right
  umbilical vein becomes
  obliterated during the 2nd
  month.
              Fate umbilical Veins
The fate of umbilical vein is:
The right umbilical and distal
  part of the left umbilical vein
  between liver and sinus
  venosus degenerate
 The persistent proximal part
  of the left umbilical vein
  becomes the Umbilical vein,
  which carries the well-
  oxygenated blood from the
  placenta to the embryo.
                Fate umbilical Veins
A large venous shunt, the Ductus
   Venosus develops within the
   liver and connects the umbilical
   vein with inferior vena cava.
   The ductus venosus forms a
   bypass through the liver so that
   most of the blood directly
   transported from the placenta to
   the heart without passing
   through the capillaries of liver
• L umbilical vein
   anastomoses with the ductus
   venosus.


                                      Before Birth   After Birth
                      Vitelline Veins
There are two vitelline veins
  in embryo, which bring the                    Sinus venosus
  deoxygenated blood from
  developing gut. The         Right umbilical
                              vein
  vitelline veins drain into
  sinus venosus. Just below                                        Liver

  the venous end of heart of
                                                                 Anastomosis
  embryo at first there is                                       b/w left and
  development of septum                                          right Cardinal
                                                                 vein
  transversum. Within the        Right & Left
  septum transversum, the        Vitelline Veins              Developing
                                                              Gut
  hepatic buds are grow from
  small intestine.
  Development of Hepatic Blood Vessels
septum transversum forms the
   stroma & blood vessels of liver.
   After passing through the
   septum transversum the vitelline             Right
   veins enter the venous end of       umbilical Vein
   the heart, the sinus venosus. As         Ductus
   the liver primorduim grows into          venosus
                                           Inferior
   septum transversum, the
                                           vena cava
   Hepatic Cords anastomose                   Right
   around pre-existing              umbilical Vein
   endothelium- spaces. These              Right
   spaces are primorduim of                Vitelline
                                           Vein
   hepatic sinusoids, later become
   linked to the vitelline veins.    Unpaired Left
                                      Umbilical Vein
  Formation of Hepatic & Portal Veins
The hepatic veins                    Anterior cardinal vein
                                   Anterior Cardinal Vein
 form from the
                                                      Left common
 remains of the Right                                 cardinal vein
 vitelline vein in the     Ductus
 region of                 venosus

 developing liver.           Inferior
                         vena Cava
 The Portal vein
                         Portal Vein                    Left
 develops from an                                       Umbilical
 anastomostic                                           Vein

 network of vitelline
 veins around the
 duodenum.
             Fate of Vitelline Veins
The part of vitelline veins in
  the region of developing
  embryo resolve into
  formation of Hepatic
                                   Ductus
  Sinusoids during the fourth      venosus
  week of development. Due       Inferior
  to development of liver the    Vena Cava
  vitelline veins divided into     Portal
  two segments, the distal         Vein
  segment from the gut to
  liver and a short proximal
                                  Left
  segment from above the          Umbilical
  liver to corresponding horn     Vein
  of sinus venosus.
         Fate of Vitelline Veins
Distal portions are
 converted into Portal
 Vein, the intermediate
 sinusoids mostly
 remain as such, but
 some part develops
 into formation of
 Ductus Venosus.
 While right proximal
 stem represent the
 Hepatic Veins
        Common Cardinal Veins
There are two common cardinal
  veins right & left.
Each common cardinal vein
  divided into Anterior cardinal
  vein bring the deoxygenated
  blood from cranial part of
  body & Posterior cardinal
  vein collects the blood from
  the caudal part of body
Ultimately the two common
  cardinal veins drain into
  respective horn of sinus
  venosus
                 Cardinal veins
The Cardinal veins
  constitute the main venous
  drainage System of
  Embryo. The anterior and
  posterior cardinal veins
  drain the cranial and
  caudal parts of embryo,
  respectively, the anterior
  and posterior cardinal
  veins join the common
  cardinal veins, which
  enter the sinus venosus.
                Cardinal Veins
During the eight week of
 development the anterior
 cardinal veins are connected
 to each other by means of an
 oblique anastomosing
 channel, that shunts the
 blood from left to right
 anterior cardinal vein. This
 anastomosing channel
 become the left
 Brachiocephalic Vein when
 the caudal part of left
 anterior cardinal vein
 degenerate.
             Subcardinal Veins
The subcardinal and
  supracardinal veins are
  gradually replace and
  supplement the posterior
  cardinal veins. The
  subcardinal vein lies
  infornt of gut. The
  subcardinal veins appear
  first and form the left
  renal vein, the suprarenal
  vein, the gonadal
  (testicular or ovarian)
  veins and a segment of
  inferior vena cava.
                Supracardinal Veins
The supracardinal veins are
  disrupted in the region of
  kidneys behind the gut.
  Cranial to this region, they
  united by an anastomosis that
  form the Azygos and the
  hepatic veins. Caudal to the
  kidneys the left suprarenal
  vein degenerates but the Right
  supracardinal become the part
  of inferior vena cava. The
  inferior vena cava is formed
  due to shunt of the blood from
  left right site of caudal part of
  embryo.
  Formation of Superior vena Cava
The superior vena cava is
  formed from the Right
  anterior cardinal vein and
  right common cardinal vein.
  Superior Vena Cava receives Subclavian
  blood from two                 Vein
  brachiocephalic Veins. Each
  Brachiocephalic Vein is
  formed by union of internal
  jugular vein and subclavian
  vein. The adult derivatives of
  the posterior cardinal veins
  are the root of azygos veins
  and common iliac veins
 Development of Inferior Vena Cava
The development of inferior vena
  cava consists four segments;
 Hepatic Segment, derived from
  the hepatic vein (proximal part
  of the right vitelline vein) and
  hepatic sinusoids.
 Prerenal segment is derived
  from the right subcardinal vein
 Renal Segment is derived from
  the subcardinal- supracardinal
  anastomosis
 Postrenal Segment is from right
  supracardinal vein
    Fate of Common Cardinal Veins
• Fate of Left Anterior
  Cardinal veins:
Proximal part of Left
  common cardinal vein
  disappears.
The Distal part takes part in
  formation of left superior
  intercostal vein and
Anastomoses with Right
  anterior cardinal vein
  distally to form Left
  brachiocephalic vein
Left common cardinal vein
  develops into oblique vein
  of left atrium
   Fate of Common Cardinal Veins
Left horn of Sinus Venosus
  Develops into Coronary
  sinus.
Right Cardinal Vein:
Anterior Cardinal Vein-
  Superior Vena Cava
Right Common Cardinal
  Vein Superior Vena
  Cava
Right Posterior Cardinal
  Vein- Root of Azygous
  Vein
Fate Cardinal Veins
Left Side   Right Side

				
DOCUMENT INFO
Description: This presentation explains the development of venous system