title: The effect of certain variables on the tumor and tissue distribution of tracers. II. Carrier effect: rapidity of onset and concentrations necessary for initiation and maximum response.
abstract: The smallest quantity of carrier Ga and Mn necessary to initiate and maximize a carrier effect was studied in the Morris 7777 rat hepatoma model. The quantity needed for a maximum response did not appear to adversely effect the rats. Not all tissues were equally affected at the same plasma concentrations. If carrier Ga was administered 2 hours following 67Ga injection and the rats sacrificed 30 minutes later, a dramatic change occurred in background activity, which was more pronounced in healthy than malignant tissues. Early viable and nonviable tumor/background ratios were improved by this technique. The data suggest that the use of carrier Ga and Mn might improve early lesion/background ratios in patients. This could be of use if tumor imaging were undertaken with 68Ga or 52mMn with positron detector systems.
mesh_terms: D000818:Animals; D005260:Female; D005709:Gallium Isotopes / Q000008:administration & dosage / Q000378:metabolism; D005710:Gallium Radioisotopes / Q000008:administration & dosage / Q000378:metabolism*; D007275:Injections, Intravenous; D007700:Kinetics; D008114:Liver Neoplasms, Experimental / Q000000981:diagnostic imaging* / Q000378:metabolism; D008297:Male; D008345:Manganese / Q000008:administration & dosage / Q000378:metabolism*; D011868:Radioisotopes / Q000008:administration & dosage; D011877:Radionuclide Imaging; D051381:Rats; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D005709:Gallium Isotopes; D005710:Gallium Radioisotopes; D011868:Radioisotopes; D008345:Manganese