European Journal of Pharmacology
February 26, 1982
C P Vandermaelen, George K. Aghajanian
37 citations
Intracellular recordings were made from facial motoneurons of anesthetized rats during systemic administration of 5-methoxy-N,-N-dimethyltryptamine (5-MeODMT) and p-chloroamphetamine (PCA), drugs which elicit the behavioral serotonin syndrome. Both drugs caused a slow depolarization, increased input resistance, and increased excitability of facial motoneurons. These changes are identical to...
Neuroscience & Biobehavioral Reviews
1982
Low intravenous doses of the hallucinogen d-lysergic acid diethylamide (LSD) markedly suppress the discharge of serotonin (5-HT)-containing neurons in the dorsal raphe nucleus of the rat. Microiontophoretically applied LSD also inhibits the firing of 5-HT neurons, indicating that the inhibitory effect is mediated directing on 5-HT neurons. Forebrain neurons receiving a major serotonergic input...
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...
European Journal of Pharmacology
November 1, 1981
Heidrun Fink, Wolfgang Oelssner
44 citations
Microinjections of LSD (0.05 microgram), mescaline (0.5 microgram) and serotonin (10 microgram) into the medial raphe nucleus of rats resulted in a strong potentiation of apomorphine (1 mg/kg i.p.)-induced hypermotility. The potentiating effect of LSD or serotonin was suppressed by simultaneous injections of methysergide (0.05 microgram) or cyproheptadine (0.05 microgram) into the medial raphe...
Journal of Neuroscience
October 1, 1981
MA Rogawaski, George K. Aghajanian
52 citations
A series of indole-ethylamines were tested for their ability to suppress the spontaneous firing of single dorsal raphe serotonergic neurons in the rat. The compounds were all derivatives of either tryptamine or N,N-dimethyltryptamine possessing hydroxy or methoxy substituents on the benzene ring portion of the indole nucleus. Their activity was assessed using quantitative microiontophoresis or...
International Journal of Quantum Chemistry
March 5, 1981
Patricia H. Reggio, Harel Weinstein, Roman Osman et al.
17 citations
In investigations of the molecular determinants for the recognition of drugs by a serotonin (5-HT) receptor in the brain, the commonality in the reactivity patterns of 5-HT congeners has been identified. On this basis a mechanistic hypothesis is proposed to explain the rank order of the affinity of drugs that bind to the receptor shared by 5-HT and LSD (the 5-HT/LSD receptor). This hypothesis...
Pharmacology, Biochemistry, and Behavior
March 1981
Richard A Glennon, D L Doot, R Young
Using an isolated rat fundus preparation, the 4-methyl (DOM), ethyl (DOET), propyl (DOPR) butyl (DOBU), tertiary butyl (DOTB) and amyl (DOAM) derivatives of 2,5-dimethoxy-phenylisopropylamine (2,5-DMA) were found to possess quite similar serotonin receptor affinities (pA2 - 7.02-7.22). The fundus preparation could not be used to determine pD2 values because all of the compounds were found to...
Pharmacology, Biochemistry, and Behavior
January 1981
T Yamamoto, S Ueki
Head-twitch induced by lysergic acid diethylamide, mescaline and 2,5-dimethoxy-4-methylamphetamine (DOM) was significantly increased by medial raphe (m-R) lesions, but dorsal raphe (d-R) lesions did not produce any changes. Hallucinogen-induced head twitch was inhibited by methysergide and tended to be increased by PCPA. These results suggest that 5-HT receptors innervated with the ascending...
Neuroscience Letters
September 1, 1980
O G Berge, K Hole, H Dahle
34 citations
The effects on pain sensitivity of intracerebroventricular injections of 5-methoxy-N,N-dimethyltryptamine were tested by the tail-flick method. Following administration of 1.6, 3.1, 6.3, 12.5 and 25 micrograms (n = 8 for each dose), tail-flick latencies were reduced by 13-24%. Fifty and 100 micrograms caused a biphasic response (hyperalgesia followed by analgesia), whereas 400 micrograms...
Psychopharmacology
1980
Richard A Glennon, R Young, John A. Rosecrans et al.
46 citations
A choice between two levers in an operant chamber was used to train 24 rats, under a variable-interval 15 s schedule of sweetened milk reinforcement, to discriminate a hallucinogenic (psychotomimetic) agent, 5-methoxy-N,N-dimethyltryptamine (5-OMe DMT), from saline administration. The 5-OMe DMT stimulus generalized in a dose-related manner to each of 14 tryptamine related analogs. With the...