Using an animal model to assess the long-term behavioral and biological consequences of adolescent abuse and exposure to alcohol.
During adolescence or adulthood, male hamster siblings were divided into control and experimental groups and exposed to periods of either mild or traumatic stress outside their individual nests. Mild stress is the simple exposure to a novel environment while the traumatic stressor is repeated daily subjugation by a dominant hamster. Over adolescence and adulthood, animals had free access to alcohol. The behavior and neuroendocrinology were assessed over these developmental periods in response to these environmental conditions. As adults, animals with a history of traumatic stress in adolescence showed inappropriate and excessive aggressive behavior. Their aggression was context dependent. In the presence of equal size hamsters, they showed little aggression; however, they were excessively aggressive toward smaller, younger animals. Testosterone levels and reproductive behavior were normal after adolescent subjugation; however, release of cortisol during agonistic encounters was suppressed. In comparison, hamsters exposed to chronic social subjugation as adults had low plasma testosterone, reduced reproductive behavior, and exaggerated cortisol release during agonistic encounters. Self-ingestion of alcohol during adolescence enhanced testosterone release around the peripubertal period but reduced plasma testosterone levels in adulthood. Exposure to alcohol as adolescents enhanced aggression in adulthood. These data demonstrate a pronounced difference in behavior and neuroendocrinology between adolescent and adult hamsters in their response to traumatic stress.
Center for Comparative Neuroimaging, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA. craig.ferris@umassmed.edu
Craig F
CF
Ferris
D000293:Adolescent; D000367:Age Factors; D000428:Alcohol Drinking / Q000523:psychology*; D000818:Animals; D006224:Cricetinae; D004195:Disease Models, Animal; D000431:Ethanol / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism*; D008297:Male; D012646:Self Administration; D012919:Social Behavior; D013315:Stress, Psychological / Q000097:blood* / Q000523:psychology*; D013739:Testosterone / Q000097:blood / Q000378:metabolism*; D013997:Time Factors
D000431:Ethanol; D013739:Testosterone; D006854:Hydrocortisone