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Angiophagy is a recently discovered mechanism of recanalization of small blood vessels in most organs. Occlusions of microvessels can occur in a large number of medical conditions and may also occur throughout life in the absence of specific pathology. The occlusions (local thrombi or emboli traveling from other locations) can be composed of a variety of materials such as blood clots, fibrin, cholesterol and calcium crystals and cell debris. Normally it is thought that enzymes in the fibrinolytic system (tissue plasminogen activator) can breakdown clots that occlude blood vessels. However, it was not clear what happened when this process failed of when occluding materials were not susceptible to enzyme breakdown.

Jaime Grutzendler and colleagues at Yale School of Medicine discovered a mechanisms they termed angiophagy, in which the blood vessel endothelium grows lamellipodia (membrane extensions) that completely surround the occluding embolus. Following this, the endothelial junctions likely open up and the occluding material is pushed out of the vessel. This process which occurs over a period of days, leads to complete vessel recanalization. The vessels ultimately survive in the long term and blood flow is reestablished.

This mechanism is likely to be very important for preventing occlusions from permanently damaging micro-vessels. This may be especially important in organs such as the brain in which the growth of new vessels (angiogenesis) is virtually absent in the adult. It has been proposed that failure of this mechanism in conditions in which micro-vessels are affected (diabetes hypertension) could lead to tissue damage and in the case of the brain could be involved in the pathogenesis of vascular dementia.