Antagonism of the LSD cue by putative serotonin antagonists: relationship to inhibition of in vivo [3H]spiroperidol binding.
In two groups of rats trained to discriminate 0.08 or 0.16 mg/kg of lysergic acid diethylamide (LSD) from saline, pirenperone and ketanserin completely blocked the stimulus effect of LSD. Pizotifen (BC-105) blocked the LSD cue when the training dose was 0.08 mg/kg, but had variable effects in the 0.16 mg/kg of LSD-trained group. The antagonism of the 0.08 mg/kg cue occurred at doses of the antagonists which blocked [3H]spiroperidol labeled 5-HT2 receptors in the frontal cortex in vivo; binding in the striatum was unaffected by the LSD antagonists. However, in doses which produce the LSD cue, neither LSD nor the 5-HT agonist, 5-methoxy-N,N-dimethyltryptamine, which substitutes for LSD, inhibited the binding in either the cortex or the striatum. The results are discussed in relation to the possible neuropharmacological basis for the LSD cue.
Nielsen
E B
EB
Ginn
S R
SR
Cunningham
K A
KA
Appel
J B
JB
D000818:Animals; D002531:Cerebellum / Q000187:drug effects; D003342:Corpus Striatum / Q000187:drug effects; D005625:Frontal Lobe / Q000187:drug effects; D007650:Ketanserin; D008238:Lysergic Acid Diethylamide / Q000494:pharmacology*; D008297:Male; D010880:Piperidines / Q000494:pharmacology; D010918:Pizotyline / Q000494:pharmacology; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000032:analysis / Q000187:drug effects*
D010880:Piperidines; D011985:Receptors, Serotonin; D010918:Pizotyline; D008238:Lysergic Acid Diethylamide; D007650:Ketanserin; C034177:pirenperone