Embriyonun Vasküler Gelişimi

Abstract

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.

Keywords

• Embriyo,vasküler,gelişim

Embryonic Vascular Plasticity

Abstract

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.

Keywords

• Embryo,vascular,development

References

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