Olfactory system damage and brain catecholamines in the rat.

Although a number of studies have reported that bulbectomy results in a fall in telencephalic norepinephrine (NE) content, the present study is the first to examine the relationship between the locus and extent of olfactory system damage and the depletion of telencephalic catecholamines after olfactory system surgery. Our findings indicate that the often reported depletion of telencephalic NE after olfactory bulb ablation is not due to removal of the olfactory bulbs per se, but instead is the result of incidentally produced destruction of tissue, caudal to the bulbs, through which noradrenergic fibers ascend on their way to various regions of the telencephalon.