Differential effects of electroconvulsive shock on four models of experimentally-induced aggression in rats

The effects of electroconvulsive shock (ECS) on the hyperemotionality and muricide in olfactory bulbectomized rats (OB rat) were compared with those in spontaneous killer rats (SP rat), raphe lesioned rats (Raphe rat) and delta 9-tetrahydrocannabinol treated rats (THC rat). Single and chronic treatment of ECS inhibited the muricide and attack response to a rod, but did not affect the struggle response to handling and flight response to air blowing. Muricide was markedly inhibited by ECS in OB and SP rats, and was moderately inhibited in THC rats, while it was slightly inhibited in Raphe rats. The present result indicates that muricide of OB rats is a useful model for evaluating antidepressant drugs as this behavior is markedly inhibited by ECS in OB rats. Furthermore, it is suggested that the effect of ECS on muricide is different depending upon the methods to induce muricide, although muricide itself seems to be behaviorally similar.