Journal of Neuroscience, Vol 4, 699-707, Copyright © 1984 by Society for Neuroscience
Locus ceruleus lesion by local 6-hydroxydopamine infusion causes marked and specific destruction of noradrenergic neurons, long-term depletion of norepinephrine and the enzymes that synthesize it, and enhanced dopaminergic mechanisms in the ipsilateral cerebral cortex
SI Harik
The local stereotaxic microinfusion of 5 micrograms of 6- hydroxydopamine
in the region of the nucleus locus ceruleus causes severe loss of
noradrenergic neurons with little evidence of nonspecific tissue reaction
or destruction that could be detected by conventional light microscopic
methods. Such lesion is accompanied by a marked and long-term depletion of
norepinephrine and comparable loss of activity of its synthesizing enzymes,
dopamine beta-hydroxylase and tyrosine hydroxylase, in the ipsilateral
cerebral cortex. Locus ceruleus lesion was also found to increase tissue
levels of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid and
homovanillic acid, in the ipsilateral cortex. These results add further
evidence to support the hypothesis that enhanced dopaminergic mechanisms
may play a central role in compensating for chronic cortical noradrenergic
denervation.