Embriyonun Vasküler Gelişimi

Yıl 2016, Cilt: 19 Sayı: 2, 114 - 116, 01.08.2016

Ahmet Çağrı Aykan , Banu Şahin Yıldız

Öz

Dolaşım sistemi, kalp ve damarlardan oluşan gelişmiş bir
sistemdir. Ekstraembriyonik mezodermden köken alan dolaşım sistemi embriyoda
fonksiyona başlayan ilk sistemdir. Anjiyoblast formasyonu ve primitif plasental
dolaşım intrauterin üçüncü hafta başında başlar. Plastisite, belli yetişkin kök
hücrelerin farklı ve çeşitli hücre tiplerine dönebilmesidir. Hematopoietik kök
hücreler beyin, kalp kası, iskelet kası ve karaciğer hücrelerine, kemik iliği
stromal hücreleri kalp kası ve iskelet kası hücrelerine dönüşebilir. Arteriyel,
venöz ya da kapiller olarak damarların tanımlanması remodeling süreciyle
yakından ilişkilidir. Arterler Ephrin-B2 ve D114, venler Ephrin-B4 ve
neurophilin-2 gibi belirteçler tarafından tanımlanmıştır. Bu genlerin
kılavuzluğunda arter ve ven tanımlanması yapılabilir. Damar dallanması bu
genler dışında, hemodinami ve kardiyak out-put düzenlenmesi ile oluşan bir
fiziksel etkene ihtiyaç duymaktadır. Akım tarafından indüklenen plastisite,
damar oluşumu için genetik ve epigenetik faktörler arasında hayati bağdır.
Arteriyel venöz farklılaşma hemodinamik kuvvetler tarafından kontrol edilir.
Sonuç olarak akım, arteriyel ağacın şekillenmesinde önemli derecede etkilidir
ve arteriyel belirteçler olan Ephrin B2 ve Neuropilin 1’in aktivasyonunu regüle
eder.

Anahtar Kelimeler

Embriyo, vasküler, gelişim

Embryonic Vascular Plasticity

Öz

The
circulatory system is a complex system containing the heart and vessels. This
system, originating from extraembryonic mesoderm, is the first functioning
system of the embryo. The formation of the angioblast and primitive placental
circulation starts at the beginning of the third week. Plasticity is defined as
the ability of a mature cell to differentiate into different cell types. Haematopoietic
stem cells can transform into neural, heart muscle, skeletal muscle and liver
cells, while the bone marrow stromal cells can transform into heart and
skeletal muscle cells. The identification of vessels as artery, venous or
capillary is closely related to remodelling. Arteries express ephrin-B2 and
D114, while veins express ephrin-B4 and neuropilin-2. With the guidance of
these genes, the identification of arteries and veins has started. Besides
genes, physical factors, including hemodynamic and cardiac output regulations,
affect vessel branching. Flow-mediated vascular plasticity is a crucial link
between the genetic and epigenetic factors. The arterial and venous
differentiations are controlled by hemodynamic factors. In conclusion, blood flow
is important for the formation of a vascular tree and activates arterial
markers, including ephrin-B2 and neuropilin-1.

Anahtar Kelimeler

Embryo, vascular, development

Kaynakça

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