Abstract:
:The authors addressed the hypothesis that interactions with creatine kinase (CK) play a role in the off-resonance magnetization transfer (MT) effect of creatine in skeletal muscle. Toward that aim, (1)H MT studies were done on hindleg muscle in wild-type mice and in transgenic mice, lacking cytoplasmic CK and/or mitochondrial CK. The (1)H MT effect was essentially identical in wild-type muscle and the two single CK knock-out muscles, while moderately decreased in tissue lacking both CK isoforms. (31)P-NMR showed no off-resonance (31)P MT effect in skeletal muscle for PCr in any of the mice, while the enzymatic CK reaction flux was circa 0.2-0.3 sec(-1) in the wild-type muscle and in muscle deficient in mitochondrial CK. The CK enzyme flux was negligible in the other two CK knock-outs. These data suggest that CK plays a minor role in the (1)H MT effect of creatine. Irrespective of the underlying mechanism the creatine MT phenomenon probably has no significant consequences for the thermodynamic availability of total creatine to the CK reaction.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Kruiskamp MJ,van Vliet G,Nicolay Kdoi
10.1002/(sici)1522-2594(200005)43:5<657::aid-mrm7>subject
Has Abstractpub_date
2000-05-01 00:00:00pages
657-64issue
5eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(200005)43:5<657::AID-MRM7>journal_volume
43pub_type
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