RETARDATION OF THE AGE-ASSOCIATED DECLINE OF IMMUNE FUNCTIONS IN AGING RATS UNDER DIETARY RESTRICTION AND DAILY PHYSICAL EXERCISE

Wistar rats were subjected to dietary restriction and daily physical e xercise for 21 months, starting from 2 months of age. At the age of 23 months, the rats were sacrificed and examined for various indices inc luding immunological functions. Body weight was almost the same betwee n rats fed ad libitum (Group A) and those (Group B) fed 80% of the die t consumed by Group A. The body weights of Groups A and B were signifi cantly heavier than that of rats (Group C) fed 60% of the diet consume d by Group A and those (Group D) which were subjected to physical exer cise and fed 80% of the diet consumed by Group A. Highly proliferative response of T cells to mitogens was observed in 5 out of 13 rats in g roup D. Some enhancement of B cell proliferation was also observed in the same rats. Present results suggested that enduring physical exerci se together with dietary restriction can retard the age-related decrem ent of immunological functions.