Increasing the selectivity of drug discrimination procedures.
In an attempt to increase the selectivity of drug discrimination, rats were trained to discriminate LSD (0.08 mg/kg) from a group of "other" compounds consisting of cocaine (10 mg/kg), pentobarbital (5 mg/kg), and saline. Acquisition of this LSD-other discrimination was rapid (31 days) in chambers equipped with retractable levers and did not differ significantly from that of a group of animals trained to discriminate LSD from saline (26 days). In substitution (generalization) tests, hallucinogens such as LSD, DMT, and DOM mimicked LSD in a dose-dependent manner in both groups. The designer drug (+/-)MDMA substituted for LSD in the LSD-other group (ED50 = 1.38) but did not substitute for the training drug in the LSD-ND group; neither (+) MDMA nor PCP mimicked LSD in either group. Most importantly, lisuride, quipazine, and yohimbine, drugs that have been described as "false positives," substituted for LSD in animals trained to discriminate LSD from saline (ED50s = 0.012, 1.662, 2.344, respectively), but not in animals trained to discriminate LSD from other drugs. Thus, the LSD-other training procedure can be described as more selective than the standard drug-ND procedure.
Appel
J B
JB
Behavioral Pharmacology Laboratory, Department of Psychology, University of South Carolina, Columbia 29208, USA.
West
W B
WB
Rolandi
W G
WG
Alici
T
T
Pechersky
K
K
D000818:Animals; D003042:Cocaine / Q000494:pharmacology; D004193:Discrimination Learning / Q000187:drug effects; D004192:Discrimination, Psychological / Q000187:drug effects*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006213:Hallucinogens / Q000494:pharmacology; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D008238:Lysergic Acid Diethylamide / Q000494:pharmacology; D008297:Male; D010424:Pentobarbital / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
D018765:Dopamine Uptake Inhibitors; D006213:Hallucinogens; D006993:Hypnotics and Sedatives; D008238:Lysergic Acid Diethylamide; D010424:Pentobarbital; D003042:Cocaine