Effects of dietary restriction on myocardial composition

From the data presented here a number of conclusions can be drawn: 1. The mass of the myocardium is quite susceptible to a moderate decrease in caloric intake. 2. Important changes in protein composition can occur. 3. The mechanisms that underly such changes are complex. One determining factor is the turnover rate of individual proteins; those with a fast turnover are affected more quickly. Other probable determining factors are the susceptibility of individual proteins to degradation and the nonlinear nature of the kinetics involved in such a process. 4. Changes in the concentration of a specific protein have to be related to changes in the mass of nonspecific protein. 5. Changes in various myocardial enzyme activities during dietary restriction are heterogeneous and diverse. 6. Diet-matched controls must be established in any study in which the appetite of the experimental animal is likely to be affected.