Journal of Neuroscience, Vol 3, 407-416, Copyright © 1983 by Society for Neuroscience
The plastic response to monocular deprivation persists in kitten visual cortex after chronic depletion of norepinephrine
MF Bear and JD Daniels
In order to clarify the role of norepinephrine (NE) in visual cortical
plasticity, we monocularly deprived kittens that had received systemic
injections of the neurotoxin 6-hydroxydopamine (6-OHDA) shortly after
birth. We found, using high pressure liquid chromatography, that this means
of drug treatment produces a permanent and substantial reduction in the
level of cortical NE as compared with littermate controls. Nonetheless,
single unit recording in area 17 of these kittens revealed no difference in
the cortical response to monocular deprivation: both drug-treated and
control kittens displayed large ocular dominance shifts to the open eye.
Because local depletion of NE by intracortical 6-OHDA in kittens can
prevent the expected ocular dominance shift after short-term monocular
deprivation, we propose that neocortex has the capacity to compensate for
chronic depletion of NE in a way which allows for the possibility of
plastic changes.