Agonist effects at putative central 5-HT4 receptors in rat hippocampus by R(+)- and S(-)-zacopride; no evidence for stereo-selectivity.
The EEG of halothane anaesthetized rats was recorded from an electrode implanted into the hippocampus. In the present study the effect of R(+)- and S(-)-zacopride, administered intra-cerebroventricularly, on different frequency bands of the EEG was investigated. Both enantiomers induced similar dose-dependent (5-20 micrograms) increases in all frequency bands. The effects of R(+)- and S(-)-zacopride were inhibited by pretreatment with a high dose of ICS 205-930 (1 micrograms i.c.v.), which suggests the involvement of 5-HT4 receptors. The lack of stereo-selectivity of the zacopride enantiomers is in contrast to observations made in in vitro studies.
Boddeke
H W
HW
Preclinical Research Sandoz Pharma Ltd, Basel, Switzerland.
Kalkman
H O
HO
D000818:Animals; D001549:Benzamides / Q000008:administration & dosage / Q000494:pharmacology*; D001643:Bridged Bicyclo Compounds / Q000008:administration & dosage / Q000494:pharmacology*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004569:Electroencephalography / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D007211:Indoles / Q000008:administration & dosage / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology*; D012702:Serotonin Antagonists / Q000494:pharmacology*; D013237:Stereoisomerism; D000077526:Tropisetron
D001549:Benzamides; D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D007211:Indoles; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D000077526:Tropisetron; C055971:zacopride