Adolescent exposure to anabolic/androgenic steroids and the neurobiology of offensive aggression: a hypothalamic neural model based on findings in pubertal Syrian hamsters.
This study examined the relationship among aggression towards lactating intruders, castration and brain GABA levels in three strains of mice (C57, C3H and CBA). Both C57 and C3H (but not CBA) animals showed reduced attack latencies following castration. C57 mice showed the highest intensity of this behavior and the response was almost absent in the CBA strain. Considerable strain differences in brain GABA levels were observed. In particular the most aggressive C57 castrates had significantly higher levels of GABA in the hypothalamus, the olfactory bulbs and the amygdala. Such changes are not recorded in C3H or CBA strains of mice, which are both characterized by low levels of baseline aggression towards lactating intruders.