title: Photoperiod reverses the effects of estrogens on male aggression via genomic and nongenomic pathways.
abstract: Despite recent discoveries of the specific contributions of genes to behavior, the molecular mechanisms mediating contributions of the environment are understudied. We demonstrate that the behavioral effects of estrogens on aggression are completely reversed by a discrete environmental signal, day length. Selective activation of either estrogen receptor alpha or beta decreases aggression in long days and increases aggression in short days. In the bed nucleus of the stria terminalis, one of several nuclei in a neural circuit that controls aggression, estrogen-dependent gene expression is increased in long days but not in short days, suggesting that estrogens decrease aggression by driving estrogen-dependent gene expression. Estradiol injections increased aggression within 15 min in short days but not in long days, suggesting that estrogens increase aggression in short days primarily via nongenomic pathways. These data demonstrate that the environment can dictate how hormones affect a complex behavior by altering the molecular pathways targeted by steroid receptors.
authors.affiliation: Department of Psychology, Institute for Behavioral Medicine Research, Ohio State University, Columbus, OH 43210, USA. bctrainor@ucdavis.edu
authors.forename: Brian C
authors.initials: BC
authors.lastname: Trainor
authors.forename: Shili
authors.initials: S
authors.lastname: Lin
authors.forename: M Sima
authors.initials: MS
authors.lastname: Finy
authors.forename: Michael R
authors.initials: MR
authors.lastname: Rowland
authors.forename: Randy J
authors.initials: RJ
authors.lastname: Nelson
mesh_terms: D000374:Aggression / Q000187:drug effects / Q000528:radiation effects*; D000818:Animals; D004967:Estrogens / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D008027:Light; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D010542:Peromyscus; D017440:Photoperiod; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012686:Septal Nuclei / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D004967:Estrogens