title: Aggression--interactions of serotonin and testosterone in healthy men and women.
abstract: Serotonin (5-HT) and testosterone (T) have both been implicated in the regulation of aggression. Findings in humans however are very inconclusive, with respect to main effects of either system. Animal models implicate T to modulate 5-HT system activity, and furthermore have shown behaviorally relevant interactions of T and 5-HT with respect to aggression. We tested for associations between habitual T-level and 5-HT system activity, as well as behaviorally relevant interactions of T and 5-HT with respect to trait aggression in 48 healthy male and female subjects. 5-HT activity was measured by means of neuroendocrine challenge paradigm with S-citalopram. T-levels were measured in saliva samples. Trait aggression was assessed by self-report measures. T-levels were not associated with indices of central 5-HT activity. Results showed significant interaction effects between 5-HT and T for trait aggression in men only (p<0.05). Trait aggression was significantly higher in the combinations "high T+high cortisol responses" (indicating decreased 5-HT availability), and "low T+low cortisol responses" (indicating increased 5-HT availability), after S-citalopram. Results support the notion of behaviorally relevant interactions between T and 5-HT, with respect to aggression in humans, but also indicate the need for further studies.
authors.affiliation: Center for Psychobiology and Behavioral Medicine, Department of Psychology, University of Giessen, Otto-Behaghel-Str. 10, D-35394 Giessen, FRG, Germany. yvonne.kuepper@psychol.uni-giessen.de
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Kuepper
authors.forename: Nina
authors.initials: N
authors.lastname: Alexander
authors.forename: Roman
authors.initials: R
authors.lastname: Osinsky
authors.forename: Eva
authors.initials: E
authors.lastname: Mueller
authors.forename: Anja
authors.initials: A
authors.lastname: Schmitz
authors.forename: Petra
authors.initials: P
authors.lastname: Netter
authors.forename: Juergen
authors.initials: J
authors.lastname: Hennig
mesh_terms: D000328:Adult; D000374:Aggression / Q000187:drug effects / Q000502:physiology*; D000704:Analysis of Variance; D015283:Citalopram / Q000494:pharmacology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis / Q000378:metabolism; D008297:Male; D010555:Personality Inventory; D012463:Saliva / Q000737:chemistry; D012701:Serotonin / Q000378:metabolism*; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology; D013739:Testosterone / Q000032:analysis / Q000378:metabolism*
chemical_list: D015283:Citalopram; D006854:Hydrocortisone; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors; D013739:Testosterone