Kopchick led a team of scientists with the university's Edison Biotechnology Institute who invented the growth hormone antagonist and the transgenic mice used in this new study. The findings suggest the use of a growth hormone antagonist or a drug that inhibits growth hormone release may help people with retinal neovascularization, said Lois Smith, professor of ophthalmology at Boston's Children's Hospital and Harvard Medical School and the lead researcher on the project. Retinal neovascularization occurs when there is an overall decrease in the number of retinal blood vessels, along with reduction in blood flow. Responding to the lack of oxygen, the retina produces new blood vessels. But unlike new blood vessel growth in other parts of the body, neovascularization in the retina can cause damage.
New vessels are prone to leakage and bleeding, which blocks light from reaching the retina.
This can lead to scarring, which may cause the retina to detach from the inside surface of the eye, leading to blindness. Abnormal retinal blood vessel growth is also the cause of blindness in retinopathy of prematurity, a condition in some babies, usually born at 30 weeks gestation or earlier, and in age-related macular degeneration in the elderly. When returned to normal air conditions, the retinas are oxygen-starved, a condition also seen in diabetic patients with proliferative retinopathy. We also saw more development of normal blood vessels in the retinas of the transgenic mice compared to the nontransgenic mice. The findings suggest a growth hormone antagonist or a drug that inhibits growth hormone release has the potential to be used to help prevent retinal neovascularization as well as a treatment for the disorder, but Smith noted more clinical studies are necessary before this group of drugs can be prescribed for patients.