title: Liposome encapsulated MnCl2 as a liver specific contrast agent for magnetic resonance imaging.
abstract: We examined the usefulness of MnCl2 entrapped in liposomes as a liver specific contrast agent for magnetic resonance imaging. Toxicity experiments showed that the effective dose for imaging experiments was 7 to 11 times lower than the LD50 of free MnCl2. In rats with implanted liver tumors, liposome encapsulated MnCl2 caused a two- to three-fold increase in the relaxation rate of the liver while having little effect on the relaxation rate of tumor tissue. T1 weighted, magnetic resonance images obtained at 0.5 T of an R3230 adenocarcinoma implanted in the liver showed an increase in the signal intensity of both normal liver and tumor tissue after the injection of free MnCl2 (25 mumole/kg). However, after the injection of liposome encapsulated MnCl2 (40 mumole/kg) the liver exhibited a marked increase in signal intensity with little change in the signal intensity of the tumor tissue. These results suggest that liposome encapsulated MnCl2 has excellent potential as a liver specific contrast agent for the improved detection of liver metastases.
authors.affiliation: Bioacoustics Research Laboratory, University of Illinois, Urbana-Champaign.
authors.forename: M R
authors.initials: MR
authors.lastname: Niesman
authors.forename: G G
authors.initials: GG
authors.lastname: Bacic
authors.forename: S M
authors.initials: SM
authors.lastname: Wright
authors.forename: H J
authors.initials: HJ
authors.lastname: Swartz
authors.forename: R L
authors.initials: RL
authors.lastname: Magin
mesh_terms: D000818:Animals; D002712:Chlorides; D003287:Contrast Media / Q000008:administration & dosage / Q000633:toxicity; D004337:Drug Carriers; D005260:Female; D008081:Liposomes; D008114:Liver Neoplasms, Experimental / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008345:Manganese / Q000008:administration & dosage; D017895:Manganese Compounds; D020149:Manganese Poisoning; D051379:Mice; D009368:Neoplasm Transplantation; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D002712:Chlorides; D003287:Contrast Media; D004337:Drug Carriers; D008081:Liposomes; D017895:Manganese Compounds; D008345:Manganese; C025340:manganese chloride