| Title: | A fighter's comeback: dopamine is necessary for recovery of aggression after social defeat in crickets |
| Address: | "Institute for Neurobiology, Free University of Berlin, Koenigin-Luise-Str. 28-30, 14195 Berlin, Germany. Institute for Biology, Leipzig University, Talstr. 33, 04103 Leipzig, Germany. Electronic address: stevenson@rz.uni-leipzig.de" |
| DOI: | 10.1016/j.yhbeh.2014.09.012 |
| ISSN/ISBN: | 1095-6867 (Electronic) 0018-506X (Linking) |
| Abstract: | "Social defeat, i.e. losing an agonistic dispute with a conspecific, is followed by a period of suppressed aggressiveness in many animal species, and is generally regarded as a major stressor, which may play a role in psychiatric disorders such as depression and post-traumatic stress disorder. Despite numerous animal models, the mechanisms underlying loser depression and subsequent recovery are largely unknown. This study on crickets is the first to show that a neuromodulator, dopamine (DA), is necessary for recovery of aggression after social defeat. Crickets avoid any conspecific male just after defeat, but regain their aggressiveness over 3 h. This recovery was prohibited after depleting nervous stores of DA and octopamine (OA, the invertebrate analogue of noradrenaline) with alpha-methyl-tyrosine (AMT). Loser recovery was also prohibited by the insect DA-receptor (DAR) antagonist fluphenazine, but not the OA-receptor (OAR) blocker epinastine, or yohimbine, which blocks receptors for OA's precursor tyramine. Conversely, aggression was restored prematurely in both untreated and amine depleted losers given either chlordimeform (CDM), a tissue permeable OAR-agonist, or the DA-metabolite homovanillyl alcohol (HVA), a component of the honeybee queen mandibular pheromone. As in honeybees, HVA acts in crickets as a DAR-agonist since its aggression promoting effect on losers was selectively blocked by the DAR-antagonist, but not by the OAR-antagonist. Conversely, CDM's aggression promoting effect was selectively blocked by the OAR-antagonist, but not the DAR-antagonist. Hence, only DA is necessary for recovery of aggressiveness after social defeat, although OA can promote loser aggression independently to enable experience dependent adaptive responses" |
| Keywords: | "Adaptation, Psychological/*drug effects Aggression/*drug effects/physiology Animals Behavior, Animal/*drug effects/physiology Competitive Behavior/drug effects Dibenzazepines/pharmacology Dominance-Subordination Dopamine/*pharmacology *Gryllidae/drug effe;" |
| Notes: | "MedlineRillich, Jan Stevenson, Paul A eng Research Support, Non-U.S. Gov't 2014/10/01 Horm Behav. 2014 Sep; 66(4):696-704. doi: 10.1016/j.yhbeh.2014.09.012. Epub 2014 Sep 28" |
