Isolation induced aggression and catecholamine variations in discrete brain areas of the mouse.

Norepinephrine (NE) and dopamine (DA) levels and turnover were measured in 17 discrete brain regions of Swiss-Webster (NIH) mice made aggressive by prolonged isolation. The NE steady state level was significantly lower in olfactory tubercle and substantia nigra and significantly higher in the septal area of the aggressive mice when compared to the isolated non-fighter controls. NE turnover was only higher in the A-10 region of the aggressors. DA steady state level and turnover was lower in olfactory tubercle and higher in caudate putamen of the aggressors. The significance of these changes in isolation-induced aggression is discussed.