Angiogenesis (angio’gen’esis) — the growth of new blood vessels — is an important natural process occurring in the body, both in health and in disease.
Angiogenesis occurs in the healthy body for healing wounds and for restoring blood flow to tissues after injury or insult. In females, angiogenesis also occurs during the monthly reproductive cycle (to rebuild the uterus lining, to mature the egg during ovulation) and during pregnancy (to build the placenta, the circulation between mother and fetus).
In the healthy body, a series of biologic “on” and “off” switches help modulate angiogenesis.
- The main “on” switches are known as angiogenesis-stimulating growth factors
- The main “off” switches are known as angiogenesis inhibitors
When angiogenic growth factors are produced in excess of angiogenesis inhibitors, the balance is tipped in favor of blood vessel growth. When inhibitors are present in excess of stimulators, angiogenesis is stopped. In general, angiogenesis is “turned off” by the production of more inhibitors than stimulators.
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