title: γ-Aminobutyric acid neural signaling in the lateroanterior hypothalamus modulates aggressive behavior in adolescent anabolic/androgenic steroid-treated hamsters.
abstract: Male Syrian hamsters (Mesocricetus auratus) treated with anabolic/androgenic steroids (AAS) during adolescence (P27-P56) display highly escalated and mature forms of offensive aggression correlated with increased γ-aminobutyric acid (GABA) afferent development as well as decreased GABAA receptors in the lateroanterior hypothalamus (LAH) - an area of convergence for developmental and neuroplastic changes that underlie offensive aggressive behaviors in hamsters. This study investigated whether microinfusion of a GABAA receptor agonist (muscimol; 0.01-1.0 pmol/l) or antagonist (bicuculline; 0.04-4.0 pmol/l) directly into the LAH modulate adolescent AAS-induced offensive aggression. Activation of LAH GABAA receptors enhanced adolescent AAS-induced offensive aggression, beginning at the 0.1 pmol/l dose, when compared with AAS-treated animals injected with saline into the LAH. Importantly, GABAA receptor agonism within the LAH significantly increased the frequency of belly/rear attacks, while simultaneously decreasing the frequency of frontal attacks. These data identify a neuroanatomical locus where GABAA receptor activation functions to enhance aggression in adolescent AAS-treated animals, while also promoting the display of mature forms of aggression and suppressing juvenile play behaviors.
authors.affiliation: Behavioral Neuroscience Program, Department of Psychology, Northeastern University, Boston, Massachusetts, USA.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Morrison
authors.forename: Lesley A
authors.initials: LA
authors.lastname: Ricci
authors.forename: Richard H
authors.initials: RH
authors.lastname: Melloni
mesh_terms: D000374:Aggression / Q000187:drug effects*; D045930:Anabolic Agents / Q000494:pharmacology; D000728:Androgens / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001640:Bicuculline / Q000008:administration & dosage / Q000494:pharmacology; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D058785:GABA-A Receptor Agonists / Q000008:administration & dosage / Q000494:pharmacology; D058787:GABA-A Receptor Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008647:Mesocricetus; D009118:Muscimol / Q000008:administration & dosage / Q000494:pharmacology; D011963:Receptors, GABA-A / Q000187:drug effects / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D045930:Anabolic Agents; D000728:Androgens; D058785:GABA-A Receptor Agonists; D058787:GABA-A Receptor Antagonists; D011963:Receptors, GABA-A; D009118:Muscimol; D005680:gamma-Aminobutyric Acid; D001640:Bicuculline