Abstract:
:Paramagnetic ions complexed to proteins may lose, retain, or enhance solvent paramagnetic relaxation (SPR) relative to free solution. We measured T1 and T2 of three mouse cancers, their normal counterparts, and six additional tissues. Long T1 of cancers was not caused by necrosis or by different contents of water, fat, or blood. Dissociable (TCA-extractable) and nondissociable (ashed) Mn, Cu, and Fe were measured by AA. Cancers had less Mn, Cu, and Fe than did normal counterparts. All 12 tissues had inverse correlations between T1 and dissociable Mn and Cu. For Mn alone to account for reduced T1, the extent to which SPR of the Mn-protein complexes would be enhanced is by factors of 0.6 to 13, below the maximum observed in Mn-enzymes. Different amounts of paramagnetic ion-protein complexes may account for part of the differences in T1 of water protons in different tissues, and the longer T1 of cancer cell water may be caused in part by reduced amounts of such complexes.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Negendank W,Corbett T,Crowley M,Kellogg Cdoi
10.1002/mrm.1910180204subject
Has Abstractpub_date
1991-04-01 00:00:00pages
280-93issue
2eissn
0740-3194issn
1522-2594journal_volume
18pub_type
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