Behavioral, Pituitary, and Adrenal Correlates of Controlled Fighting (Defeat) in Mice

Abstract

Male C57BL/10J mice, when exposed to trained fighters at the rate of 4 1-min. exposures for 0-8 days, showed the following: decreasing cumulative fighting times as the experiment progressed; progressively increasing adenohypophy-seal ACTH [adrenocorticotropic hormone] content and adrenal weight; increased plasma corticosterone levels and no change in relative adrenal corticosterone content. A 2nd experiment gave tentative results suggesting that adrenal weight may increase following exposure to the presence of a fighter (no physical contact) providing the animal had previously experienced a series of defeats by a fighter.