BACKGROUND Previous research has shown that plasma creatine levels are influenced by extracellular concentrations of insulin and glucose as well as by the intracellular creatine concentration. However, the form of creatine administered does not appear to have any effect although specific data on this is lacking. This study examined whether the administration of three different forms of creatine...

After the daily administration of methyltestosterone to normal human subjects for several weeks, creatine usually appears in the urine in gradually increasing amounts (1,2). Because the creatinuria so induced is associated with an increase in the concentration of serum creatine, and also because the amount of urinary creatinine increases, it has been generally assumed that the synthesis of crea...

Impairment or interruption of oxygen supply compromises brain function and plays a role in neurological and neurodegenerative conditions. Creatine is a naturally occurring compound involved in the buffering, transport, and regulation of cellular energy, with the potential to replenish cellular adenosine triphosphate without oxygen. Creatine is also neuroprotective in vitro against anoxic/hypoxi...

A large number of studies have been published on creatine supplementation over the last decade. Many studies show that creatine supplementation in conjunction with resistance training augments gains in muscle strength and size. The underlying physiological mechanism(s) to explain this ergogenic effect remain unclear. Increases in muscle fiber hypertrophy and myosin heavy chain expression have b...

Profound alterations in myocellular creatine and phosphocreatine levels are observed during human heart failure. To maintain its intracellular creatine stores, cardiomyocytes depend upon a cell membrane creatine transporter whose regulation is not clearly understood. Creatine transport capacity in the intact heart is modulated by substrate availability, and it is reduced in the failing myocardi...

Although it is well established that only two enzymes, transamidinase and guanidoacetate methylpherase, are directly involved in the formation of creatine (l-4), almost nothing is known about the regulation of creatine synthesis. Since various diseases alter creatine metabolism (5), it is possible that a study of transamidinase and guanidoacetate methylpherase activities in some of these diseas...