The Journal of Neuroscience, January 1, 2003, 23(1):12-16
BRIEF COMMUNICATION
Chronic Cocaine Self-Administration Upregulates the
Norepinephrine Transporter and Alters Functional Activity in the
Bed Nucleus of the Stria Terminalis of the Rhesus Monkey
Darrel J.
Macey,
Hilary R.
Smith,
Michael A.
Nader, and
Linda J.
Porrino
Center for the Neurobiological Investigation of Drug Abuse,
Department of Physiology and Pharmacology, Wake Forest University
Health Sciences, Winston-Salem, North Carolina 27157
The bed nucleus of the stria terminalis (BNST) is in a key position
to influence the integration of motivational and visceral functions,
receiving inputs from limbic regions, including the amygdala, and
sending projections to areas central to reward processing, including
the ventral tegmental area and nucleus accumbens. The BNST also
possesses a high density of noradrenergic fibers. The purpose of the
present studies was to characterize the effects of cocaine
self-administration on the regulation of norepinephrine transporter
(NET) distribution and functional activity in the BNST of rhesus
monkeys in the initial (5 d) or chronic (100 d) phases of cocaine
self-administration. NET binding site densities in the BNST were
assessed with quantitative in vitro receptor autoradiography using [3H]nisoxetine, and rates of
local cerebral glucose utilization in the BNST were measured in
the same monkeys using the 2-[14C]deoxyglucose
method. Chronic exposure to cocaine self-administration resulted in
significantly higher NET binding site densities (up to 52% relative to
controls) throughout the BNST. Furthermore, cerebral metabolism was
depressed significantly in a time-dependent manner with larger
decreases after 100 d of cocaine self-administration. These data
represent the first report of significant changes in the regulation of
the NET resulting from cocaine exposure in primates. Furthermore, given
the role of the BNST in cocaine withdrawal and stress-related
reinstatement of self-administration, the changes reported here may
provide a substrate for these phenomena.
Key words:
cocaine; self-administration; bed nucleus of the
stria terminalis; norepinephrine; receptor autoradiography; local
cerebral glucose utilization
Copyright © 2003 Society for Neuroscience 0270-6474/03/23112-05$05.00/0