CORRELATION BETWEEN CARDIAC-MUSCLE MYOSIN ATPASE ACTIVITY AND VELOCITY OF MUSCLE SHORTENING

Although an interrelationship between the maximum velocity of muscle shortening and the maximum rate of ATP hydrolysis of myosin ATPase has been postulated, the only established correlation has been in skeletal and smooth muscle from a variety of animal species. The present study employed conditions known to alter contractile function of the heart and determined that a statistically significant (n = 24, P < 0.01) relationship exists between the maximum rate of ATP hydrolysis and the maximum velocity of papillary muscle shortening in the myocardium of a single species. © 1979.