Stress can reduce blood flow to the brain

We are talking about nNOS-type neurons of the first type, which make up less than 1% of all brain cells. Despite their rarity, they play a key role — they regulate the constriction and expansion of blood vessels, ensuring a stable supply of oxygen and nutrients to the brain.

The scientists removed these neurons from laboratory mice and noticed a significant decrease in cerebral blood flow and neuron activity. “The arteries and veins of the brain are constantly pulsating, as if pumping fluid and helping to supply oxygen to the brain. When we destroyed these cells, this pulsation abruptly weakened,” explained the head of the study, Professor Patrick Drew.

Experiments have also shown that these neurons are particularly vulnerable to prolonged stress. Even moderate stressful situations led to their death, and with them, to a decrease in the activity of the entire brain. The greatest disturbances were observed during sleep, which indicates that nNOS neurons may play an important role in the recovery processes of the brain at night.

According to Drew, stress, not just aging, may be one of the causes of impaired cerebral circulation and an increased risk of neurodegenerative diseases. In the future, the team plans to find out how the loss of these cells interacts with the genetic factors of Alzheimer’s disease and other forms of dementia.