Changes in basic cardiovascular activities during the lifetime of the rat.

In an effort to characterize rats as animal models for aging research, literature dealing with cardiovascular physiology and structure has been reviewed, and available data has been summarized in tabular form. The approach has been to present functional parameters on the basis of rat strain, age, sex, and experiemental condition, in the cases where these are known, so as to develop a unified reference source of baseline data. Hemodynamic properties, such as heart rate, cardiac output, blood pressure and related vascular parameters, have been found to change during the lifetime of rats in such a way as to make the cardiovascular system less efficient in meeting organismal requirements with increasing age. At the cellular level, changes in structure, electrophysiology, and contractile properties have been reported which could account, at least in part, for observed deterioration in cardiovascular function during aging.