Olfactory bulbectomy: Neural structures involved in irritability and aggression in the male rat.

Abstract

Performed bilateral ablations of the main olfactory bulbs of 12 male hooded rats (main OB group), of the main and accessory bulbs of 21 Ss (OB + AOB group), of the bulbs and areas caudal to the bulbs of 20 Ss (supra-OB group), and of the caudal areas only on 9 Ss (caudal group). Sham bulbectomy was performed on 7 Ss, and 8 controls were unoperated. The supra-OB and caudal groups became extremely irritable and the OB + AOB group somewhat irritable, while the main OB group was unchanged in irritability. Mouse killing increased within all groups. Postoperative irritability, but not killing, was highly correlated with extent of brain damage, while killing was correlated with irritability. It is concluded that bulbectomy-induced irritability is dependent upon damage to areas within and caudal to the bulbs to which the stria terminalis projects, and that both the irritability and killing are the result of altering a common motivational mechanism. (52 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved)