Adrenergic mechanisms in rabbit olfactory bulb

Abstract

Antidromic stimulation of mitral cell axons in the lateral olfactory tract (LOT) produces inhibition of mitral cells in the ipsilateral olfactory bulb, presumably through activation of recurrent axon collaterals. In decerebrate rabbits, electrophoretic administration of norepinephrine (NE), acetylcholine (ACh), or serotonin (5-HT) to individual mitral cells decreases their discharge rate. By means of electrophoretic administration of known antagonists of ACh, NE, and 5-HT as well as of intravenous administration of drugs that deplete brain stores of NE, 5-HT, and dopamine, evidence was obtained favoring a close functional correlation between NE or a related substance and the LOT inhibitory response.