It is well known'-4 that a considerable fraction of the total creatine in heart muscle is present in such a form that upon extraction by conventional procedures, such as trichloroacetic or perchloric acid, it will react directly with the diacetyl reagent. It is conventionally called the free creatine fraction and amounts to about 7 mM per kg of rabbit heart muscle.4 The concentration of free cr...

Our present knowledge of the chemical behavior of creatine in muscle tissue rests largely upon the discovery of phosphocreatine by Fiske and Subbarow in 1927 (1). However, prior to this time there were many observations that suggested an interrelationship between creatine and other substances present in muscle. Urano (2) had already pointed out in 1906 the interesting fact that in experiments i...

The abnormalities in regional function produced by myocardial ischemia persist after the ischemic episode resolves. Since a close functional coupling exists between myofibrillar creatine kinase and myosin ATPase, a disruption of this coupling could adversely influence myocardial function and might provide a mechanism for the myocardial dysfunction observed. The purpose of the present study was ...

PURPOSE Angiotensin-converting enzyme (ACE) inhibitors show beneficial long-term hemodynamic effects in chronically infarcted hearts. The purpose of this study was to test whether prevention of the deterioration of mechanical function by ACE inhibitors is related to beneficial effects on high-energy phosphate metabolism that is deranged in heart failure. METHODS Twelve-week old rats were rand...