It's just about OK normally, but when anything else happens to decrease brain blood flow, oxygen levels in the hippocampus reduce to levels that stop neurons from working. We think that's probably why Alzheimer's disease first causes memory problems- because the early decrease in blood flow stops the hippocampus from working properly. "Now we want to discover whether the lower blood flow and oxygen levels in the hippocampus are what causes beta-amyloid to start to build up in Alzheimer's disease. Also, when neurons are active, there is a large increase in blood flow and oxygen levels in the visual cortex. "The scientists also found that blood vessels in the hippocampus contained fewer mRNA transcripts (codes for making proteins) for proteins that shape blood vessel dilation.

Source: Economic Times May 29, 2021 12:38 UTC