Do-Geun Kim and colleagues at the Korea Brain Research Institute in Daegu, South Korea, found that perivascular spaces are significantly narrower in mice modelling Alzheimer’s disease than in healthy ones. The research team studied two groups of mice, including one group genetically engineered to express five mutations associated with Alzheimer’s in humans.
Researchers injected a dye into the cisterna magna to observe fluid movement. In healthy mice, the dye spread along the outside of arteries and into brain tissue during the first 30 minutes before disappearing almost entirely by 120 minutes.
Conversely, the dye in genetically modified mice accumulated around the outsides of the arteries with little reaching brain tissue. Kim said, "The passage is somewhat blocked."
The dye in the modified mice brains mostly ended up in amyloid plaques. Cholesterol fluorescence declined after 5 minutes in healthy mice, but the cholesterol signal increased up to 120 minutes in the modified mice.
Maiken Nedergaard at the University of Rochester in New York said, "The perivascular spaces are the highway for fast fluid inflow." Roslyn Bill at Aston University in Birmingham, UK, said, "I would regard this more as a hypothesis-generating piece."
