Features of Changes in the Velocity Indicators of Cerebral Blood Flow in Rats at Different Stages of Aging

Abstract

Changes in the velocity of cerebral blood flow can make a significant contribution to the formation of age-related cerebrovascular diseases. The age-related changes in the velocity indicators of cerebral blood flow in rats at different stages of aging were studied. Using Doppler ultrasound the state of blood flow in the cortex and subcortical structures of the cerebral hemispheres was analyzed by the value of linear velocities and blood flow indexes in young Sprague-Dawley 4-month-old and aging 18 and 23-month-old rats. It has been established that aging is accompanied by changes in the parameters of cerebral blood flow in the cortex and subcortical structures of the rat brain. Changes develop gradually and differ at different stages of aging. By 18 months, perfusion in the frontal and parietal regions hemispheres of the brain increases due to an increase in peak and mean velocity per cardiac cycle and a decrease in the level of resistance of cerebral vessels. These processes precede the development of subsequent hypoperfusion disorders of blood flow observed at later stages of aging. Hypoperfusion changes in 23-month-old rats are most pronounced in the frontal region of the cerebral hemispheres and are characterized by a decrease in peak velocities and an increase in blood flow indexes.