ABSTRACT
Increased oxidative stress with increasing age is a source of damage to cellular structure and function. Tissue with few or no cell divisions, such as heart is theoretically more susceptible to accumulative damage caused by oxidative stress. The purpose of this study was to investigate the effect of age progression on apoptosis rate of rat hearts. In this experimental study, Forty eight male Wistar rats [three months old and body mass of 230 +/- 14 g] were randomly assigned to four groups, 6, 9, 12 and 15 months of age. Six hearts of each group were assigned to apoptosis analysis by TUNEL method and fixed in 10% formalin. Six remaining hearts of each group were washed out and homogenized in ice cold buffer and the supernatant were assigned to apoptosis analysis by ELISA method. The results of TUNEL and ELISA apoptosis detection showed that the rates of apoptosis were increased with age in 12 and 15 months groups compared to 6 months rats [p<0.05 and p<0.01, respectively]. Moreover the results of TUNEL method depicts a significant increase in apoptosis rate in 9 months group compared to 6 months group [p<0.05]. These results suggest that the age of animals might be important factor in the increase of the heart apoptosis rate