title: Effect of TRX-liposomes size on their prolonged circulation in rats.
abstract: Newly formulated cationic liposomes (TRX-liposomes) with four different mean diameters were injected into twelve male rats via the lateral tail vein in order to evaluate the effect of liposomal size on pharmacokinetic parameters. TRX-liposomes disappeared from the blood according to the one-compartment model and demonstrated maximum and minimum half-lives of ca. 14 h (mean diameter of 114.3 nm) and ca. 5 h (mean diameter of 285.9 nm), respectively. This prolonged half-life tended to decrease at the boundary of 114.3 nm mean diameter. The optimal size (114.3 nm) for prolonged circulation of TRX-liposomes was consistent with that of pegylated liposomes such as Doxil((R)), however, the half-life was different among these liposomes. The electric charge of the TRX-liposomal surface is assumed to be responsible for this difference. The results of the present study will be very useful in the design of long-circulating cationic liposomes.
authors.affiliation: R&D Center, Terumo Corporation, Kanagawa, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kawahara
authors.forename: Arinobu
authors.initials: A
authors.lastname: Sekiguchi
authors.forename: Emiko
authors.initials: E
authors.lastname: Kiyoki
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Ueda
authors.forename: Kyoko
authors.initials: K
authors.lastname: Shimamura
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kurosaki
authors.forename: Shozo
authors.initials: S
authors.lastname: Miyaoka
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Okabe
authors.forename: Masaharu
authors.initials: M
authors.lastname: Miyajima
authors.forename: Junji
authors.initials: J
authors.lastname: Kimura
mesh_terms: D000818:Animals; D001550:Benzamidines / Q000097:blood* / Q000737:chemistry* / Q000493:pharmacokinetics; D001775:Blood Circulation / Q000187:drug effects / Q000502:physiology; D005227:Fatty Acids / Q000097:blood* / Q000737:chemistry* / Q000493:pharmacokinetics; D008081:Liposomes; D008297:Male; D010316:Particle Size; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: C450860:3,5-dipentadecyloxybenzamidine hydrochloride; D001550:Benzamidines; D005227:Fatty Acids; D008081:Liposomes