Messaging by flow in the brain
Flow map in the third ventricle of the mouse brain. We have all bumped our heads at some point, and such incidents are usually harmless. This is thanks to fluid-filled chambers in our brain that offset minor knocks and jolts and provide padding for sensitive components of our nervous system. Cerebral fluid, however, has more than just a protective function: It removes cellular waste, supplies our nervous tissue with nutrients, and transports important messenger substances. How these messenger substances are actually being delivered to their destination in the brain, however, was unclear until now. Göttingen-based Max Planck researchers have now discovered that tiny cilia on the surface of specialized cells could lead the way. Through synchronized beating movements, they create a complex network of dynamic flows that act like conveyor belts transporting molecular "freight". The results obtained by the scientists suggest that these flows send messenger substances directly...