Neuroendocrine Regulation of Aggression: A Synthesis of Rodent, Avian, and Primate Studies

An import role for gonadal steroid hormones, particularly testosterone, in mediating aggressive behavior is well‐established across vertebrate taxa. Due to the emphasis placed on testosterone much less is know regarding the potential role of other steroid and peptide hormones in the regulation of aggression. The idea that any single hormone mediates aggression, however, is overly simplistic. In fact, research over the last two decades or more have has suggested that aggression in a complex behavior that is regulated by a wide range of hormones in addition to testosterone. This chapter reviews several novel neuroendocrine mechanisms that have been recently identified as being implicated in the regulation of aggressive behavior. Specific focus is placed on studies conducted in rodents, birds and primates, as the majority of research in this area has focused on these groups of animals. List of Abbreviations: ACTH, adrenocorticotropic hormone; ADHD, attention deficit hyperactivity disorder; AE, androstenedione; ALLO, allopregnanolone; AR, androgen receptor; Aromatase, cytochrome P450 aromatase; AVP, arginine vasopressin; AVT, arginine vasotocin; BERKO, estrogen receptor b knock‐ out; BNST, bed nucleus of the stria terminalis; CNS, central nervous system; CORT, cortisol; 5a‐DHT, 5a‐dihydrotestosterone; DHEA‐S, dehydroepiandrosterone sulfate; DHEA, dehydroepiandrosterone; E1, estrone; E2, 17b‐estradiol; ER, estrogen receptor; ERKO, estrogen receptor knock‐out; GABA, gamma‐ aminobutyric acid; 17b‐HSD, 17b‐hydroxysteroid dehydrogenase; 3b‐HSD, 3b‐hydroxysteroid dehydrogenase/isomerase; HP, hippocampus; HPA, hypothalamo‐pituitary‐adrenal; LD, light:dark; LH, luteinizing hormone; MPOA, medial preoptic area; N, nidopallium; NCM, caudomedial nidopallium; P450c17, cytochrome P450 17a‐hydroxylase/C17,20 lyase; P450scc, cytochrome P450 side chain cleavage; POA, preoptic areaPREG, pregnenolone; PROG, progesterone; RA, robust nucleus of the arcopallium; STI, simulated territorial intrusion; T, testosterone; Tn, nucleus taeniae of the amygdala; TP, testosterone propionate; VMN, ventromedial nucleus