DESTRUCTION OF LOCUS-COERULEUS NEURONAL PERIKARYA AFTER INJECTION OF ANTI-DOPAMINE-B-HYDROXYLASE IMMUNOTOXIN INTO THE OLFACTORY-BULB OF THERAT

Saporin, a ribosome-inactivating protein, was coupled to a monoclonal antibody to dopamine-B-hydroxylase (DBH) and injected unilaterally int o 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 sur viving LC neurons on the side ipsilateral to the immunotoxin-injected olfactory bulb. The number of Nissl-positive LC neurons in a transvers e section through the caudal one third of the LC was reduced from 116 +/- 10 to 50 +/- 8 neurons (P < 0.01, n = 7) and the number of DBH-pos itive neurons in the more rostral LC sections was reduced from 13 +/- 2 to 5 +/- 1 (P < 0.05, n = 4). Our results indicate that it is possib le to lesion LC neurons via retrograde intraaxonal transport of sapori n-anti-DBH immunotoxin from the olfactory bulb. (C) 1998 Published by Elsevier Science Ireland Ltd.