On the State of Creatine in Heart Muscle

A Study of Creatine Metabolism in Diseases Causing Muscle Wasting *

“…This is made evident by the different of 13 to 23 days. Although all of these diseases specific activities of urine creatine anid creatinine cause creatinuria and low concentrations of in two of our patients ( Figure 1 ) and by the muscle creatine, the defects in the metabolism of findings of Benedict and associates (10 (30).…”

Presence of (phospho)creatine in developing and adult skeletal muscle of mice without mitochondrial and cytosolic muscle creatine kinase isoforms

“…The present results also bear on the issue of MR visibility of the cellular Cr pool, and the presumed existence of significant free‐Cr pools that do not participate in the CK reaction. Based on experiments using 14 C‐labelled Cr in heart muscle (Lee & Visscher, 1961; Savabi, 1988) and in fast twitch muscle of fish (Hochachka & Mossey, 1998) it has been proposed that a significant fraction of Cr (about 30 %) is not immediately available for the CK reaction in these tissues. MR magnetization transfer experiments on skeletal muscle indeed revealed a pool of Cr that may be bound to matrix or cellular macromolecules, but this pool is in exchange with ‘mobile’, MRS‐visible creatine and comprises only about 2 % of total creatine (Kruiskamp et al 1999; Renema et al 2002).…”

Roles of creatine in the regulation of cardiac protein synthesis

“…In this case, the creatine concentration is increased about twofold, and it is this transient change in creatine concentration which is postulated to lead to increased contractile protein synthesis. If creatine is found in several intracellular compartments, as suggested by Lee and Visscher (7), local changes in concentration may be even greater then twofold. A specific effect on contractile protein synthesis seems reasonable in light of the work of Rabinowitz (13) and of Page et al (11), among others, showing disproportionate accumulation of myofibrillar and mitochondrial proteins in response to work-induced hypertrophy and thyroxin-stimulated growth.…”