Most people assume that all busy nerve cells, or neurons, signal nearby blood vessels to replenish themselves. (sciencenews.org)
If the uterus contracts too strongly, it can press against nearby blood vessels, cutting off the supply of oxygen to the muscle tissue of the uterus. (my.clevelandclinic.org)
Cancer cells and tumors at first rely on nearby blood vessels to get what they need to survive, but, as tumors grow, they need to form new vessels. (sciencedaily.com)