Abstract
Gerontologists are concerned about obesity for 2 reasons. First, adiposity increases in humans with increasing age. Secondly, the interaction between obesity and aging may be deleterious. Since rats are a widely used animal model for the study of aging, it is likely that rats will be utilized in experiments designed to study the interactions between adiposity and aging. The object of this review is to provide the basic information needed for utilizing rats in such studies. To this end, changes in adipose tissue mass that occur during the life span of normal rats are described as are the types of rat models that have been used in the study of obesity. The characteristics of each of these obesity models are detailed.