two days after an experimental whiplash performed on anesthetized long-evans female rats , without any direct blow to the head , we observed : ( 1 ) a hypotension ( in supine position ) ( p less than 0.01 ) , ( 2 ) a disturbance of the postural regulation of cerebral blood flow ( p less than 0.01 ) , ( 3 ) a disturbance of learning behavior characterized by decreased acquisition and retention ( conditioned avoidance response and labyrinth tests ) , ( 4 ) an increase of the dopamine level ( whole brain , cerebellum , thalamus + hypothalamus , corpus striatum and rest ) , ( 5 ) a decrease of the noradrenaline level in whole brain ( p less than 0.05 ) and in the medulla oblongata but an increase in thalamus plus hypothalamus , hippocampus and corpus striatum , ( 6 ) an increased reactivity of the peripheral alpha and beta receptors , determined by analyzing the hemodynamic consequences of i.v . injection of norepinephrine or isoproterenol , ( 7 ) there was no modification of the brain content of water or of serotonin and ( 8 ) finally , the injured rats displayed a remarkably aggressive behavior , though this was not quantified .
C0020649
hypotension
C0013030
dopamine