In vivo kinetics and displacement study of a carbon-11-labeled hallucinogen, N,N-[11C]dimethyltryptamine.
The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [11C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [11C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [11C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors.
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002247:Carbon Isotopes; D004285:Dogs; D007700:Kinetics; D008297:Male; D004130:N,N-Dimethyltryptamine / Q000378:metabolism; D011868:Radioisotopes; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000000981:diagnostic imaging; D014018:Tissue Distribution; D014025:Titanium; D014055:Tomography, Emission-Computed; D014363:Tryptamines
D002247:Carbon Isotopes; D011868:Radioisotopes; D011985:Receptors, Serotonin; D014363:Tryptamines; D014025:Titanium; D004130:N,N-Dimethyltryptamine