title: A distribution study of 11C platelet-activating factor (PAF) analogs in normal and tumor-bearing mice.
abstract: As a preliminary study to image platelet-activating factor (PAF) receptors in vivo, comparative study of biodistribution between 1-O-hexadecy1-2-O-N, N-dimethylcarbamoyl-sn-glycero-3-phosphocholine [choline-methyl-11C](L-[11C]dimethylcarbamoyl-PAF) and nonspecific PAF analog, 3-O-hexadecyl-2-O-N,N-dimethylcarbamoyl-sn-glycero-1-phosphocholine [choline-methyl-11C](D-[11C]-dimethylcarbamoyl-PAF) was carried out in both normal and tumor-bearing mice. Higher accumulation of L-[11C]dimethylcarbamoyl-PAF than D-[11C]dimethylcarbamoyl-PAF was observed in normal mice spleen. The co-administration of PAF antagonists dose-dependently reduced the radioactivity level of the L-isomer only in the spleen. In mice bearing Ehrlich tumors and Sarcoma 180, more L-than the D-[11C]-isomer was accumulated in the tumor and spleen. We found that specific accumulation sites for L-[11C]dimethylcarbamoyl-PAF exist in the spleen and tumors than in other tissues. Moreover, the comparison of accumulation between L- and D-[11C] dimethylcarbamoyl-PAF would be a useful procedure for estimation of PAF receptors in vivo.
authors.affiliation: Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sasaki
authors.forename: T
authors.initials: T
authors.lastname: Tohyama
authors.forename: K
authors.initials: K
authors.lastname: Oda
authors.forename: H
authors.initials: H
authors.lastname: Toyama
authors.forename: S
authors.initials: S
authors.lastname: Ishii
authors.forename: M
authors.initials: M
authors.lastname: Senda
authors.forename: K
authors.initials: K
authors.lastname: Karasawa
authors.forename: N
authors.initials: N
authors.lastname: Satoh
authors.forename: M
authors.initials: M
authors.lastname: Setaka
authors.forename: S
authors.initials: S
authors.lastname: Nojima
authors.forename: T
authors.initials: T
authors.lastname: Nozaki
authors.forename: P
authors.initials: P
authors.lastname: Braquet
mesh_terms: D000818:Animals; D002250:Carbon Radioisotopes; D007700:Kinetics; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010972:Platelet Activating Factor / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000493:pharmacokinetics; D010980:Platelet Membrane Glycoproteins / Q000032:analysis* / Q000378:metabolism; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D012016:Reference Values; D012510:Sarcoma 180 / Q000378:metabolism*; D013237:Stereoisomerism; D014018:Tissue Distribution
chemical_list: C102274:1-O-hexadecyl-2-O-N,N-dimethylcarbamoyl-sn-glycero-3-phosphocholine; D002250:Carbon Radioisotopes; D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C039351:platelet activating factor receptor