Species variations in RU 24969 interactions with non-5-HT1A binding sites.
The interaction of RU 24969 with [3H]5-hydroxytryptamine ([3H]5-HT) binding to non-5-HT1A binding sites was analyzed in nine species. Non-5-HT1A binding was defined as specific [3H]5-HT binding observed in the presence of 100 nM 8-OH-DPAT. Computer-assisted iterative curve fitting of RU 24969 competition studies indicate that RU 24969 distinguishes two distinct components of non-5-HT1A sites in rat and mouse brain. These two binding components display apparent Ki values of 0.33-0.39 and 66-130 nM for RU 24969. By contrast, RU 24969 competition for non-5-HT1A binding in guinea-pig, cow, human, dog, chicken, turtle and frog brain membranes is consistent with a homogeneous population of [3H]5-HT binding sites. This population of sites displays apparent Ki values of 23-130 nM for RU 24969 and appear to be analogous to the low affinity component of non-5-HT1A sites identified in rat and mouse.
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001667:Binding, Competitive / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D002417:Cattle; D002645:Chickens; D004285:Dogs; D006168:Guinea Pigs; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D007700:Kinetics; D051379:Mice; D008807:Mice, Inbred BALB C; D011894:Rana pipiens; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000378:metabolism*; D013045:Species Specificity; D013764:Tetrahydronaphthalenes / Q000494:pharmacology; D014426:Turtles
D007211:Indoles; D011985:Receptors, Serotonin; D013764:Tetrahydronaphthalenes; C025145:5-methoxy 3-(1,2,3,6-tetrahydro-4-pyridinyl)1H indole; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin