Hepatic contrast-enhancing properties of manganese-mesoporphyrin and manganese-TPPS4. A comparative magnetic resonance imaging study in rats.
OBJECTIVE
Manganese (III) mesoporphyrin (Mn-mesoporphyrin), a synthetic and stable complex, was investigated for its hepatic magnetic resonance imaging (MRI) properties and compared with manganese tetrakis-(4 sulfonatophenyl) porphyrin (Mn-TPPS4).


METHODS
Liver abscesses (n = 10) and tumors (n = 14) were induced in rats. These rats then underwent MRI at 2.0 T. Animals received one of the two contrast agents, and measurement of lesion enhancement was performed.


RESULTS
At an intravenous dose of 0.035 mmol/kg, Mn-mesoporphyrin caused significant enhancement of normal liver parenchyma and increased the lesion-to-liver contrast in both the models of heptic liver abscess and metastatic liver disease. Mn-TTPS4 at an intravenous dose of 0.04 mmol/kg typically enhanced both lesion and normal liver parenchyma and therefore did not improve the lesion-to-liver contrast.


CONCLUSIONS
The hepatotrophic properties of Mn-mesoporphyrin indicate its potential as an intravenous contrast agent for liver imaging.
Schmiedl
U P
UP
Department of Radiology, University of Washington, School of Medicine, Seattle 98195.
Nelson
J A
JA
Starr
F L
FL
Schmidt
R
R
D000818:Animals; D003287:Contrast Media; D005260:Female; D008100:Liver Abscess / Q000175:diagnosis*; D008113:Liver Neoplasms / Q000175:diagnosis / Q000556:secondary*; D008279:Magnetic Resonance Imaging; D008652:Mesoporphyrins; D008665:Metalloporphyrins; D051381:Rats; D011916:Rats, Inbred F344; D011919:Rats, Inbred Strains
D003287:Contrast Media; D008652:Mesoporphyrins; D008665:Metalloporphyrins; C067090:manganese mesoporphyrin; C056661:manganese(III)tetraphenylporphine sulfonate