J Neurophysiol 91: 2628-2648, 2004. Melanie T. Wyder, Dino P.
Massoglia and Terrence R. Stanford
Three rhesus monkeys (Macaca mulatta) were prepared for chronic
single-unit recording. Each monkey underwent two sterile surgical
procedures while under general isoflurane anesthesia. During the first
surgery, an MRI-compatible titanium post was attached to the skull using
titanium screws and orthopedic bone cement. Also at this time, a
preformed loop of Teflon-coated stainless steel wire (eye coil) was
implanted beneath the conjuctiva to circumscribe the cornea of one eye
(Judge et al. 1980). During subsequent training/recording sessions, the
post served to restrain the monkey's head, whereas the eye coil provided
an analog signal of eye position (Fuchs and Robinson 1966; Robinson
1963). Recovery from the initial surgery required 2�4 wk, during which
time analgesics and antibiotics were administered as required.
Fully recovered animals were trained on the behavioral task (see
following text). Once trained to a criterion level of performance, a
second surgery was performed to place an MRI-compatible recording
cylinder (Crist Instrument) over the oculomotor thalamus (OcTh). A
presurgical MRI was carried out to optimize the stereotaxic coordinates
of the cylinder for individual monkeys. The recording cylinder was
positioned over a small craniotomy (about 15 mm diameter) and secured
with titanium screws and bone cement. Daily recording sessions began on
full recovery (2�3 wk).
Cocaine Self-Administration Produces a Progressive Involvement of
Limbic, Association, and Sensorimotor Striatal Domains
The Journal of Neuroscience, April 7, 2004, 24(14):3554-3562 -- Linda
J. Porrino, David Lyons, Hilary R. Smith, James B. Daunais, and Michael
A. Nader
Subjects. Fourteen experimentally naive adult male rhesus monkeys (Macaca
mulatta) weighing between 7.6 and 11.5 kg (mean � SD; 9.5 � 1.04) at the
start of the study served as subjects. Monkeys were housed individually
in stainless steel cages with water ad libitum; animals had physical and
visual contact with each other. Their body weights were maintained at
90�95% of free-feeding weights by banana-flavored pellets earned during
the experimental sessions and by supplemental feeding of Lab Diet Monkey
Chow, provided no sooner than 30 min after the session. All procedures
were performed in accordance with established practices as described in
National Institutes of Health Guide for Care and Use of Laboratory
Animals. In addition, all procedures were reviewed and approved by the
Animal Care and Use Committee of Wake Forest University.
Behavioral apparatus. Cocaine self-administration and food-reinforced
responding occurred in ventilated and sound-attenuated operant chambers
(1.5 x 0.74 x 0.76 m; Med Associates, East Fairfield, VT) designed to
accommodate a primate chair (Model R001, Primate Products, Redwood City,
CA). The chamber contained an intelligence panel (48 x 69 cm), which
consisted of two retractable levers (5 cm wide) and three stimulus
lights. The levers were positioned within easy reach of the monkey
sitting in the primate chair. One gram of food pellets was delivered
from a feeder located on the top of the chamber. A peristaltic infusion
pump (7531�10, Cole-Parmer Co., Chicago, IL) was used to deliver drug
injections at a rate of 1 ml/10 sec to those animals self-administering
cocaine.
See also : Wake Forest University,
Winston-Salem, NC