TY - JOUR
T1 - First- versus last-session substitution
T2 - An evaluation of the reinforcing effects of cocaine and the cocaine analogue 2β-propanoyl-3β-(4-tolyl)-tropane
AU - Lile, Joshua A.
AU - Morgan, Drake
AU - Nader, Michael A.
PY - 2000
Y1 - 2000
N2 - Research has shown that many variables influence the reinforcing effects of drugs. The purpose of the present study was to compare the reinforcing effects of cocaine and the long-acting cocaine analogue 2β-propanoyl-3β-(4-tolyl)-tropane (PTT) in rhesus monkeys during the 1st versus the last day of substitution. When PTT and cocaine were initially substituted for food or the training dose of cocaine, a large number of injections were self-administered. However, when the 1st day of substitution was compared with the last day, the number of injections obtained with PTT but not cocaine were significantly lower. This effect was observed under different schedule conditions and in cocaine-naive and cocaine-experienced monkeys. These results suggest that when studying long-acting cocaine analogues, unlike cocaine itself, quantitative differences may be seen early in substitution testing compared with stable performance after multiple-session substitution.
AB - Research has shown that many variables influence the reinforcing effects of drugs. The purpose of the present study was to compare the reinforcing effects of cocaine and the long-acting cocaine analogue 2β-propanoyl-3β-(4-tolyl)-tropane (PTT) in rhesus monkeys during the 1st versus the last day of substitution. When PTT and cocaine were initially substituted for food or the training dose of cocaine, a large number of injections were self-administered. However, when the 1st day of substitution was compared with the last day, the number of injections obtained with PTT but not cocaine were significantly lower. This effect was observed under different schedule conditions and in cocaine-naive and cocaine-experienced monkeys. These results suggest that when studying long-acting cocaine analogues, unlike cocaine itself, quantitative differences may be seen early in substitution testing compared with stable performance after multiple-session substitution.
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U2 - 10.1037/1064-1297.8.3.424
DO - 10.1037/1064-1297.8.3.424
M3 - Article
C2 - 10975634
AN - SCOPUS:0033736233
SN - 1064-1297
VL - 8
SP - 424
EP - 433
JO - Experimental and Clinical Psychopharmacology
JF - Experimental and Clinical Psychopharmacology
IS - 3
ER -