RESPONSE OF NEUROGENIC AMINES TO AGGREGATION AND STRANGERS

¹ Department of Psychiatry, University of Utah College of Medicine, Salt Lake City, Utah

Aggregation of mice who were strangers to one another resulted in a decrease in brain norepinephrine and an increase in its rate of catabolism. Serotonin levels remain unchanged, although concentration of 5-hydroxyindoleacetic acid in brain increased, indicating an increased catabolism of serotonin as well. Dopamine levels in brain and its catabolism were unaffected. At the same time no changes in norepinephrine metabolism could be detected in the adrenal, heart or spleen. The intermingling of strangers without aggregation also decreased brain norepinephrine. A more severe stress of footahock to rats not only diminished brain norepinephrine but also radically reduced catecholamine levels in the adrenal and spleen. These observations suggest that emotional disturbances activate the norepinephrine and serotonin systems in brain. In the case of norepinephrine these changes are first detectable in brain, but a more intense activation produces a further reduction of brain norepinephrine, now associated with decreases in norepinephrine in the peripheral organs.