Destruction of locus coeruleus neuronal perikarya after injection of anti-dopamine-B-hydroxylase immunotoxin into the olfactory bulb of the rat

Saporin, a ribosome-inactivating protein, was coupled to a monoclonal antibody to dopamine-B-hydroxylase (DBH) and injected unilaterally into the olfactory bulb of rats. After 4–13 days survival, the rat brain was processed histologically and the locus coerulei (LC) examined with Nissl and anti-DBH staining. There were degenerating dendrites in surviving LC neurons on the side ipsilateral to the immunotoxin-injected olfactory bulb. The number of Nissl-positive LC neurons in a transverse section through the caudal one third of the LC was reduced from 116±10 to 50±8 neurons ( P