The effects of serotonergic compounds on evoked responses in the dentate gyrus and CA1 region of the hippocampal formation of the rat.
The effects of serotonin (5-HT), the 5-HT1A receptor subtype agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and the 5-HT2 receptor subtype agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on electrophysiological responses in the dentate gyrus and area CA1 were examined in the in vitro hippocampal slice preparation. Superfusion of either serotonin or 8-OH-DPAT in the bath was found to inhibit population responses in a dose-dependent manner in both regions, with a greater effect in the CA1. The effects of 8-OH-DPAT in both regions were attenuated significantly by the serotonergic antagonist methysergide, as were the effects of 5-HT on the population spike in the CA1. The application of DOI did not produce statistically significant effects in either region. These findings support an inhibitory role for the 5-HT1A receptor in both area CA1 and the dentate gyrus.
Klancnik
J M
JM
Department of Psychology, University of British Columbia, Vancouver, Canada.
Obenaus
A
A
Phillips
A G
AG
Baimbridge
K G
KG
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000662:Amphetamines / Q000494:pharmacology*; D000818:Animals; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects*; D066298:In Vitro Techniques; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D008784:Methysergide / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects*; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D000662:Amphetamines; D011985:Receptors, Serotonin; D013764:Tetrahydronaphthalenes; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D007650:Ketanserin; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine; D008784:Methysergide