Effect of exercise training on livers of young, old, and ovariectomized rats

Abstract

The menopause is a mid life event, characterized by estrogenic deficiency and associated with bio-psycho and social changes which impair quality of life. In addition, exercise can be described as a body activity that enhances or maintains physical fitness and overall life quality. This experiment was conducted to determine if exercise training has a protective role against the deleterious effects of aging in ovariectomized rats. In this study, thirty-six Wistar albino rats were used. The rats were divided into six subgroups. Subgroups consisted of young rats, old rats, ovariectomized rats, young exercise-trained rats, old exercise-trained rats and ovariectomized exercise-trained rats. Control rats and ovariectomized rats 12 weeks after surgery were subjected to a 4 week treadmill-running program. In exercise groups, the rats were subjected to treadmill exercise during the time each rat walked on a motor-driven treadmill for 15 m min-1 speed and 15° incline once every 2 days for a period of 10 days over three courses for 5, 10 and 15 mins per day, totally for 30 days. In the stereological analysis of this study, the numerical density of the control groups were found significantly higher compared to ovariectomized and/or training groups (p<0.05). On the other hand, the liver cell numbers of ovariectomized exercise-trained group was found to be lesser than other trained and ovariectomized groups. In addition, the cell density of ovariectomized group estimated as a little higher than other groups except for control group (p<0.05).The stereological results revealed that ovariectomy and training can decrease the hepatocyte density in ovariectomized rats.

Keywords

• Exercise
• Hepatocyte
• Menopause
• Rats
• Stereology

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