Abstract: | The immobilization- and sound stimulus-induced changes in cerebral circulation were studied in spontaneously hypertensive rats. It was found that there was a stress-induced increase in the levels of epinephrine and norepinephrine in brain tissue, which was associated with lower levels of vasoactive prostaglandins E and F2 and with their imbalance with vasodilator prostaglandins E being prevalent. The change in the cerebral ratio of biologically active substances results in cerebral blood flow autoregulation failure and development of large cerebral hemorrhages. |