An attempt to separate the roles of corticosterone and ACTH in the control of post-shock fighting behaviour in male laboratory mice.

One experiment was conducted to separate the roles of corticosterone and ACTH in the mediation of the facilitatory effects of experiencing shock on subsequent fighting behaviour in male mice. It was found that (1) treatment with electric foot-shock and single injections of ACTH (one dose level) lead to comparable increases in subsequent fighting in intact males; (2) preventing changes in testosterone secretion by combined castration and testosterone replacement does not occlude or modify the facilitatory effects of shock or ACTH on subsequent fighting; and (3) preventing changes in both testosterone and corticosterone secretion by combined castration-adrenalectomy and testosterone-corticosterone replacement prevents shock and ACTH induced increases in fighting. These findings suggest that corticosterone plays a more important role than ACTH in the mediation of the facilitatory effects of shock on subsequent fighting behaviour in male mice.