Effects of intermittent buprenorphine administration on cocaine self-administration by rhesus monkeys.
In previous studies, daily buprenorphine administration significantly reduced cocaine self-administration by rhesus monkeys over 15 to 120 days (Mello et al., 1990, 1992). This report describes the effects of 60 days of intermittent buprenorphine (0.40 mg/kg) treatment once every 48 hr or 72 hr on cocaine and food self-administration by six rhesus monkeys. Cocaine (0.05 or 0.10 mg/kg/injection) and food (1-g banana pellet) self-administration were maintained on a fixed ratio 4, (variable ratio 16:S) reinforcement schedule. Intermittent buprenorphine treatment reduced cocaine self-administration significantly below saline treatment levels (P < .01). On the first day of buprenorphine treatment, cocaine self-administration averaged 53 and 60% below base line (P < .01-.0001). Cocaine self-administration remained significantly below base line on day 2 (P < .02-.0001) but usually returned to base-line levels by day 3. During buprenorphine treatment once every 48 hr, cocaine self-administration gradually increased over time in four monkeys (P < .001-.0005). These data suggest that intermittent buprenorphine treatment is less effective than daily buprenorphine treatment in reducing cocaine self-administration by rhesus monkeys. Food self-administration decreased by 23.6 and 12.7% from the saline base line during buprenorphine treatment every 48 and 72 hr, respectively. On the day of buprenorphine treatment, food self-administration was usually significantly lower than during the saline base line (P < .05-.0001), but usually returned to or exceeded base line levels by days 2 and 3. There were no significant changes in food self-administration over time with intermittent buprenorphine treatment every 48 hr.
Mello
N K
NK
Alcohol and Drug Abuse Research Center, Harvard Medical School-McLean Hospital, Belmont, Massachusetts.
Kamien
J B
JB
Lukas
S E
SE
Mendelson
J H
JH
Drieze
J M
JM
Sholar
J W
JW
D000818:Animals; D002047:Buprenorphine / Q000008:administration & dosage* / Q000097:blood / Q000494:pharmacology; D003042:Cocaine / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D004435:Eating; D005260:Female; D008253:Macaca mulatta; D008297:Male; D012646:Self Administration
D002047:Buprenorphine; D003042:Cocaine