The effects of 8-hydroxy-2-(di-n-propylamino)tetralin and other serotonergic agonists on performance in a radial maze: a possible role for 5-HT1A receptors in memory.
A group of ten rats was trained to obtain food pellets in an 8-arm radial maze. The effects of pretreatment with (+)-Lysergic acid diethylamide (+)-tartrate (LSD), m-trifluoromethylphenylpiperazine (TFMPP), 5-methoxy-N,N-dimethyltryptamine oxalate (5-MeO-DMT), racemic 8-hydroxy-2-(di-n-propylamino)tetralin HBr (8-OH-DPAT), and 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-indole succinate (RU 24969) were then evaluated. All drugs were administered IP 15 min before testing. With the exception of an increased rate of responding at a dose of 0.1 mg/kg of 8-OH-DPAT, all drugs produced a dose-related decline in response rate. In addition, LSD, RU 24969, and 8-OH-DPAT caused a statistically significant decrease in efficiency of responding. Of the three, 8-OH-DPAT was clearly the most active. Doses of 0.3, 1.0, and 3.0 mg/kg resulted in efficiencies of 61%, 53%, and 44%, respectively. The present results taken in light of 8-OH-DPAT's preferential binding to 5-HT1A receptors, the high density of these receptors in hippocampus, and the observation that the number of 5-HT1A receptors is decreased in Alzheimer's disease, suggest a possible role for this serotonergic receptor subtype in memory.
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D007211:Indoles / Q000494:pharmacology; D008238:Lysergic Acid Diethylamide / Q000494:pharmacology; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D008732:Methoxydimethyltryptamines / Q000494:pharmacology; D009281:Naphthalenes / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology*; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D007211:Indoles; D008732:Methoxydimethyltryptamines; D009281:Naphthalenes; D010879:Piperazines; D011985:Receptors, Serotonin; D013764:Tetrahydronaphthalenes; C018406:1-(3-trifluoromethylphenyl)piperazine; C025145:5-methoxy 3-(1,2,3,6-tetrahydro-4-pyridinyl)1H indole; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D008238:Lysergic Acid Diethylamide