Study Provides Insight into How the Brain Regulates Its Blood Flow

Researchers have demonstrated, for the first time, that the vascular endothelium plays a critical role in the regulation of blood flow in response to stimulation in the living brain. To tease apart the role of endothelial signaling in the living brain, they had to develop new ways to both image the brain at very high speeds, and also to selectively alter the ability of endothelial cells to propagate signals within intact vessels, which the team achieved through a range of techniques that use light and optics. Focused laser light was used in combination with a fluorescent dye within the bloodstream to cause oxidative damage to the inner endothelial layer of blood brain arterioles, while leaving the rest of the vessel intact and responsive. The team showed that, after damaging a small section of a vessel using their laser, the vessel no longer dilated beyond the damaged point. When the endothelium of a larger number of vessels was targeted in the same way, the overall blood flow response of the brain to stimulation was significantly decreased. “We think we’ve found a missing link in our understanding of how the brain dynamically tunes its blood flow to stay in sync with the activity of neurons,” says Elizabeth M. C. Hillman, associate professor of biomedical engineering at Columbia University. To learn more about the study, click here.