title: Organ distributions of liposome-loaded rat platelets.
abstract: Past in vitro functional assays have demonstrated that platelet function is not inhibited by liposome uptake. In the present study, the organ distributions of control and liposome-loaded Sprague-Dawley rat platelets were examined to determine whether liposome uptake enhances RES uptake. Platelets were isolated using STRactan density gradient centrifugation, incubated with small unilamellar liposomes in vitro for 1 hour, labeled with 51Cr and injected into a cohort group of rats. One hour post-injection the spleen, liver, lungs, blood, kidneys and bladder contents were removed and the percentages of the recovered dose localized per total organ (%RD) were determined. The RES index, defined as %RDliver + %RDspleen, were 24.8 +/- 4.5 and 20.5 +/- 5.0 for the control platelets and liposome-loaded platelets, respectively. These results indicate that liposome uptake does not enhance RES uptake.
authors.affiliation: Department of Chemistry, California Institute of Technology, Pasadena.
authors.forename: R
authors.initials: R
authors.lastname: Male
authors.forename: D G
authors.initials: DG
authors.lastname: Moon
authors.forename: J S
authors.initials: JS
authors.lastname: Garvey
authors.forename: W E
authors.initials: WE
authors.lastname: Vannier
authors.forename: J D
authors.initials: JD
authors.lastname: Baldeschwieler
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000166:cytology / Q000502:physiology*; D002469:Cell Separation / Q000379:methods; D002499:Centrifugation, Density Gradient; D002784:Cholesterol / Q000031:analogs & derivatives; D002860:Chromium Radioisotopes; D008081:Liposomes / Q000378:metabolism* / Q000493:pharmacokinetics; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013154:Spleen / Q000378:metabolism; D014018:Tissue Distribution; D014316:Tritium
chemical_list: D002860:Chromium Radioisotopes; D008081:Liposomes; D014316:Tritium; C035237:3-O-(1-hexadecyl)cholesterol; D002784:Cholesterol