Media Advisory
Wednesday May 29, 2024
An NIH-funded study challenges conventional wisdom about cerebral blood flow.
What
Researchers have, for the first time, visualized the entire network of blood vessels across the cortex of awake mice, finding that blood vessels expand and contract in a rhythmic manner, leading to “waves” crossing the surface of the brain. These findings, funded by the National Institutes of Health (NIH), improve understanding of how the brain receives blood, although the function of the waves remains a mystery.
A network of elastic, actively pumping vessels carrying oxygenated blood crosses the surface of the brain before entering the cortex. There, they feed a second network of capillaries that deliver oxygen deeper into the tissues. Using experimental methods and physics-based analyses, researchers found that in addition to pulses of blood flow that occur with each heartbeat, slower waves of changes in blood flow pass through the brain and occur approximately every ten seconds. The change in blood flow caused by these slow waves accounted for up to 20% of the brain’s total blood supply. Surprisingly, this phenomenon was only weakly linked to changes in brain activity.
The waves produce visible bulges in blood vessels, making it easier for fluid to mix around brain cells. This has implications for how waste and other materials are removed from the fluid surrounding brain cells. Since waves of bulging blood vessels move in various directions, the authors speculate that the pulses of dilation and contraction of blood vessels are more likely to participate in mixing the fluid around them rather than actively moving it in one direction. given. Regardless, this mixing activity could help clear misfolded proteins and other components from the brain into the surrounding spinal fluid. This process is considered an important protective mechanism against various neurological disorders, such as Alzheimer’s disease and other related dementias, and is most active during sleep.
These findings may also affect current approaches to interpreting fMRI scans, which measure changes in blood oxygenation in brain structures as they are activated. Specifically, the finding that these waves of blood flow changes occur largely independently of brain activity suggests a new level of complexity that must be considered when interpreting the link between fMRI data and activation. cerebral.
This research was funded in part by the NIH Brain research through the advancement of innovative neurotechnologies® (BRAIN) Initiative (U19NS123717, R01NS108472), the NIH National Institute of Neurological Disorders and Stroke (R35NS097265), the NIH National Institute of Mental Health (R01MH111438), and the National Institute of Biological Imaging and Bioengineering from NIH (U24EB028942, R01EB026936)
WHO
Jim Gnadt, Ph.D., program director, NINDS Division of Neurosciences
Roderick Corriveau, Ph.D., program director, NINDS Division of Neurosciences
To arrange an interview, please contact NINDSPressTeam@ninds.nih.gov.
Article
Broggini T., J. Duckworth et al. “Long-wavelength progressive vasomotion waves modulate cortex perfusion.” Neuron. May 22, 2024. DOI: 10.1016/j.neuron.2024.04.034
About the National Institute of Neurological Disorders and Stroke (NINDS): NINDS is the nation’s leading funder of brain and nervous system research. The mission of NINDS is to seek fundamental knowledge about the brain and nervous system and to use this knowledge to reduce the burden of neurological disease.
The NIH BRAIN initiative is managed by 10 institutes and centers whose current missions and research portfolios complement the goals of the BRAIN Initiative®: National Center for Complementary and Integrative Health, National Eye Institute, National Institute on Aging, National Institute on Alcohol Abuse and Alcoholism, National Institute of Biomedical Imaging and Bioengineering, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute on Drug Abuse, National Institute on Deafness and Other Communication Disorders, National Institute of Mental Health, and National Institute of Neurological Disorders and Stroke.
About the National Institutes of Health (NIH):The NIH, the nation’s medical research agency, is comprised of 27 institutes and centers and is part of the U.S. Department of Health and Human Services. The NIH is the primary federal agency that conducts and supports basic, clinical, and translational medical research, and studies the causes, treatments, and cures for common and rare diseases. For more information about the NIH and its programs, visit www.nih.gov.
NIH…Transforming discovery into health®
News Source : www.nih.gov
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