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In questo tipo di formazione dei vasi, la parete [[capillare]] si estende nel [[lume]] per dividere un unico vaso in due. Si osservano quattro fasi nell'intussuscezione. In primo luogo, le due pareti opposte capillare istituire una zona di contatto. In secondo luogo, le giunzioni delle cellule endoteliali vengono riorganizzati e il doppio strato vaso è forato per consentire fattori di crescita e cellule di penetrare nel lume. In terzo luogo, un nucleo si forma tra le due nuove navi nella zona di contatto che è pieno di periciti e miofibroblasti. Queste cellule, che iniziano le fibre di collagene nel nucleo di fornire una matrice extracellulare per la crescita del lume del vaso. Infine, il nucleo è integrato con alterazioni alla struttura di base. Intussuscezione è importante perché si tratta di una riorganizzazione di cellule già esistenti. Permette un notevole aumento del numero di capillari senza un corrispondente aumento del numero di cellule endoteliali. Questo è particolarmente importante nello sviluppo embrionale, come non ci sono abbastanza risorse per creare un microcircolo ricco di cellule nuove ogni volta che una nuova nave sviluppa.

Intussusception, also known as '''splitting angiogenesis''', was first observed in neonatal rats. In this type of vessel formation, the [[capillary]] wall extends into the [[lumen]] to split a single vessel in two. There are four phases of intussusceptive angiogenesis. First, the two opposing capillary walls establish a zone of contact. Second, the [[endothelial cell]] junctions are reorganized and the vessel bilayer is perforated to allow growth factors and cells to penetrate into the lumen. Third, a core is formed between the two new vessels at the zone of contact that is filled with [[pericyte]]s and [[myofibroblasts]]. These cells begin laying [[collagen]] fibers into the core to provide an [[extracellular matrix]] for growth of the vessel lumen. Finally, the core is fleshed out with no alterations to the basic structure. Intussusception is important because it is a reorganization of existing cells. It allows a vast increase in the number of [[capillaries]] without a corresponding increase in the number of [[endothelial cell]]s. This is especially important in embryonic development as there are not enough resources to create a rich microvasculature with new cells every time a new vessel develops.

==Note==

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'''Intussusception''' is the process whereby a new [[blood vessel]] is created by the splitting of an existing blood vessel in two. It is one of the three ways that blood vessels are known to be formed in the human body, the other two being [[angiogenesis]] and [[vasculogenesis]].

Intussusception, also known as '''splitting angiogenesis''', was first observed in neonatal rats. In this type of vessel formation, the [[capillary]] wall extends into the [[lumen]] to split a single vessel in two. There are four phases of intussusceptive angiogenesis. First, the two opposing capillary walls establish a zone of contact. Second, the [[endothelial cell]] junctions are reorganized and the vessel bilayer is perforated to allow growth factors and cells to penetrate into the lumen. Third, a core is formed between the two new vessels at the zone of contact that is filled with [[pericyte]]s and [[myofibroblasts]]. These cells begin laying [[collagen]] fibers into the core to provide an [[extracellular matrix]] for growth of the vessel lumen. Finally, the core is fleshed out with no alterations to the basic structure. Intussusception is important because it is a reorganization of existing cells. It allows a vast increase in the number of [[capillaries]] without a corresponding increase in the number of [[endothelial cell]]s. This is especially important in embryonic development as there are not enough resources to create a rich microvasculature with new cells every time a new vessel develops.

== References ==