Psychopharmacology
1988
L D Chait, S M Evans, K A Grant et al.
The discriminative stimulus (DS) effects of smoked marijuana were studied by training marijuana smokers to discriminate between the effects of marijuana containing 2.7% delta 9-THC (M) and marijuana containing 0.0% delta 9-THC (P). In addition to measures of discrimination responding, subjective effects were assessed with standardized mood questionnaires. The post-smoking increase in expired...
Psychopharmacology
1988
S S Wang, C A Mathis, S J Peroutka
R(-)-2,5-Dimethoxy-4-77Br-amphetamine [77Br-R(-)DOB], a radioligand of high specific activity (1500 +/- 200 Ci/mmol), was used to label membrane-associated recognition sites in rat brain. 77Br-R(-)DOB sites were of high affinity (KD = 0.19 nM) but low density (Bmax = 0.32 pmol/g tissue) in rat brain preparations. Competition experiments show that both 5-hydroxytryptamine (5-HT) and 5-HT2...
Psychopharmacology
1988
T G Aigner
The effects of orally administered delta-9-tetrahydrocannabinol (THC) were evaluated on two different learning abilities in monkeys. Visual recognition memory, known to depend on limbic system integrity, was tested by means of delayed nonmatching-to-sample and found to be significantly impaired by acute administration of 2 and 4 mg/kg THC given 1 or 2 h prior to testing. Performance was...
Psychopharmacology
1988
C B Hubner, M Bird, S Rassnick et al.
3,4-Methylenedioxymethamphetamine (MDMA) is a psychoactive phenylisopropylamine which is structurally similar to both amphetamine-related sympathomimetics and the hallucinogen, mescaline. MDMA produces pleasurable effects which include euphoria, and recent reports continue to demonstrate its widespread recreational use. The aim of the present study was to assess the effects of racemic MDMA on...
Psychopharmacology
1988
M Titeler, R A Lyon, Richard A Glennon
Alterations in brain serotonergic function have been implicated in the mechanism of action of LSD, mescaline, and other similarly acting hallucinogenic drugs of abuse such as STP (2,5-dimethoxyphenylisopropylamine; DOM). In order to test the hypothesis that the mechanism of action of LSD and phenylisopropylamine hallucinogens is through stimulation of a specific brain serotonin receptor...
Psychopharmacology
November 1, 1987
M. Davis
23 citations
The ability of serotonin2 (5-HT2) antagonists to block the excitatory effects of mescaline on the acoustic startle reflex were analyzed. Mescaline (20 mg/kg) caused a consistent increase in the amplitude of the acoustic startle reflex. This effect was blocked in a dose-related fashion by the 5-HT2 antagonist ritanserin (ED50 dose = 0.25 mg/kg IP). In contrast, even a high dose of ritanserin...
Psychopharmacology
1987
Kathryn A. Cunningham, J. B. Appel
84 citations
The neuropharmacological mechanisms underlying the behavioral effects of d-lysergic acid diethylamide (LSD) were assessed by comparing the discriminative stimulus properties of LSD with those of agonists and antagonists that act selectively at putative serotonin (5-hydroxytryptamine; 5-HT) receptor subtypes (5-HT1 and 5-HT2). Male Sprague-Dawley rats (N = 23) were trained to discriminate LSD...
Psychopharmacology
1987
D G Spencer, T Glaser, J Traber
69 citations
Male Wistar rats were trained to discriminate the interoceptive effects of 5-methoxy-N,N-dimethyltryptamine (5-OMe-DMT; 1.25 mg/kg, IP) from saline in a two-lever operant chamber. Following discrimination learning, the following drugs (with ED50 dose in mg/kg IP) dose-dependently generalized: lysergic acid diethylamide (LSD, 0.04), 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT, 0.11),...
Psychopharmacology
1987
G T Shearman, L Tolcsvai
8 citations
The effect of the selective 5-HT3 receptor antagonists ICS 205-930 and MDL 72222 on head shaking behavior induced by L-5-HTP and behavioral symptoms induced with 5-methoxy-N,N,-dimethyltryptamine (5-MeODMT) in rats was evaluated. Both drugs dose-dependently reduced L-5-HTP-induced head shaking but were at least 600 times less potent than pirenperone and ketanserin and at least 50 times less...
Psychopharmacology
1987
R J Lamb, Roland R. Griffiths
MDMA (d,1-3,4-Methylenedioxymethamphetamine HCl; "ecstasy") self-injection (0.1-3.2 mg/kg/injection) was examined in baboons under conditions in which baseline responding was maintained by intravenous injections of cocaine HCl (0.32 mg/kg/injection). Drug was available under a FR 160-response schedule of intravenous injection. Each drug injection was followed by a 3-h time out allowing a...
Psychopharmacology
1987
W D Hooker, R T Jones
The marijuana-induced acute memory impairment was assessed in a double-blind, crossover experiment. Twelve males smoked NIDA-supplied cigarettes containing 1.2% delta-9-tetrahydrocannabinol (THC) or cannabinoid-exhausted marijuana (placebo) in counterbalanced order on 2 days 1-3 weeks apart. Practice, pre- and postsmoking test sessions were conducted with the Paced Auditory Serial Addition...
Psychopharmacology
1986
E T Iwamoto
The effects of phencyclidine (PCP) on locomotor activity were compared to those of the stereoisomers of N-allylnormetazocine (NAN) after acute administration to rats. PCP produced swaying and falling movements, increased sniffing behavior, and enhanced horizontal locomotor activity. d-NAN also induced swaying, falling, sniffing behavior and locomotion, and decreased rearing behavior. l-NAN...
Psychopharmacology
1986
R A Lyon, Richard A Glennon, M Titeler
3,4-Methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxy-amphetamine (MDA), and their optical isomers, were assayed for their affinities at radiolabeled brain serotonin (5-HT1, 5-HT2) and dopamine (D2) binding sites. (R(-)-MDA and R(-)-MDMA displayed moderate affinities for 3H-ketanserin-labeled 5-HT2 sites (Ki = 3425 and 3310 nM, respectively) whereas the affinities for their...
Psychopharmacology
1985
M T Schütz, J C De Aguiar, F G Graeff
161 citations
Microinjection of 5, 10, and 20 nmol serotonin (5-HT) and of 0.5, 1, and 2 nmol 5-methoxy-N, N-dimethyltryptamine (5-MeODMT) into the dorsal midbrain of rats bearing chronically implanted chemitrodes raised the electrical threshold for inducing escape behaviour following stimulation of the dorsal periaqueductal grey matter (DPAG). Linear regressions of log dose against drug-induced increase in...
Psychopharmacology
1985
P C Moser, P H Redfern
33 citations
The intensity of the head-twitch response and the 5-hydroxytryptamine (5-HT) syndrome (tremor, fore-paw treading, head-weaving and hind-limb abduction) was measured in male CFLP mice following IP injection of 5 mg/kg 5-methoxy-N,N-dimethyltryptamine (5-MeODMT). The results of separate experiments carried out at 1.5-h intervals throughout the light-dark cycle showed a clear circadian variation...
Psychopharmacology
1985
E B Nielsen, J B Appel
Rats were trained to press a lever under a variable-interval (VI) schedule of water reinforcement. After stable responding had developed, a 4.5-KHz tone (CS) was conditioned classically to a 2.5-mA electric shock (US) in groups of animals which had been given various psychoactive drugs or saline. Twenty-four hours later, a stimulus generalization test was conducted in the absence of drug;...
Psychopharmacology
1985
Françis C. Colpaert, Theo Meert, C J Niemegeers et al.
The newly synthesized compound and putative 5-HT2 antagonist ritanserin, but not the structurally related compound R 56413, resembles pirenperone in that it acts as a pure antagonist in an LSD-saline drug discrimination assay in the rat. Ritanserin exceeded pirenperone in terms of behavioral specificity; the lowest effective dose of ritanserin in antagonizing LSD was one order of magnitude...
Psychopharmacology
1984
B W Lex, J H Mendelson, S Bavli et al.
The effects of marijuana cigarette (1.8% THC) smoking on pulse rate and mood were studied under double-blind placebo-controlled conditions in 28 adult female volunteers during the follicular, luteal, and ovulatory phases of the menstrual cycle. Statistically significant increases in pulse rate, subjective levels of intoxication, and the POMS confusion factor occurred after marijuana smoking....
Psychopharmacology
1984
J H Mendelson, N K Mello
The reinforcing properties of delta 9THC (17.5 mg), a 1 g marijuana cigarette containing 1.83% delta 9-THC, a synthetic cannabis compound (Nabilone 2 mg orally), and their respective placebos were assessed with self-report and operant work-contingent choice procedures. Three groups of eight subjects were selected on the basis of a history of regular, intermittent, or occasional...
Psychopharmacology
1984
M E Carroll, D C Stotz
Six monkeys were trained to self-administer orally delivered phencyclidine (0.25 mg/ml) under a fixed-ratio 16 (FR-16) schedule. Water was concurrently available under an FF-16 schedule. During initial phencyclidine training, three monkeys were allowed free access to food (food satiation) and three were maintained at 85% of their free-feeding body weights (food deprivation). At the end of the...
Psychopharmacology
1983
R Young, John A. Rosecrans, Richard A Glennon
25 citations
The discriminative effects of 5-methoxy-N,N-dimethyltryptamine (5-OMeDMT) were studied in rats trained to discriminate 1.5 mg/kg or 3.0 mg/kg 5-OMeDMT from saline. A series of antagonist and generalization tests revealed that (1) antagonism of the 5-OMeDMT stimulus response by the presumed serotonin antagonist BC-105 depended on the dose of 5-OMeDMT, (2) the 5-OMeDMT stimulus generalized to...
Psychopharmacology
June 1, 1982
Lynne M. Adams, Mark A. Geyer
A free exploration test was used to examine the effects of LSD on investigatory responding and locomotor activity in a novel environment. Rats were injected with 20–30 μg/kg LSD or saline prior to being placed in a home cage. After 10 min, a door was opened permitting entry into a larger holeboard chamber where crossovers, rearings, hole pokes, and routes of locomotion were monitored. When...
Psychopharmacology
March 1, 1982
Randall L. Commissaris, Richard H. Rech
The effects of diazepam quipazine, lysergic acid diethylamide (LSD), and 2,5-dimethoxy-4-methylamphetamine (DOM) were examined on a conditioned suppression paradigm. Food-deprived rats were trained to drink a liquid diet from a tube. Subsequently, intermittent 7-s tones were presented during the daily 10-min sessions, the tube being electrified during the last 5 s of each tone. The subject...
Psychopharmacology
February 1, 1982
Jon Koerner, James B. Appel
19 citations
Fifteen rats were trained to discriminate between the tryptamine hallucinogen psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine; 1.0 mg/kg) and saline in a two-lever choice task. Dose-response and time-response curves were obtained. The psilocybin cue generalized to psilocin (the dephosphorylated congener of psilocybin) and to the prototypical indoleamine hallucinogen LSD, but not to the...
Psychopharmacology
1982
I Lucki, A Frazer
91 citations
The serotonin syndrome, a behavioral response produced by the activation of serotonin receptors, and 3H-serotonin binding were examined after repeated treatment of rats with different types of antidepressant drugs. The serotonin syndrome was produced by the direct-acting serotonin receptor agonists 5-methoxy-N,N-dimethyltryptamine (5-MeDMT) or d-lysergic acid diethylamide (LSD). Repeated, but...