The effect of the decreasing pattern of exercise intensity during taper period on the immunohistochemical expression of caspase-3 in pneumocytes of type I and II in young Rats' lung

The aim of the present study was to investigate the effect of taper intensity on the expression of caspase-3 in type I and II pneumocytes in the lung of young male wistar rats.

In the study, 30 five-week-old male wistar rats were randomly divided into two groups of fifteen (control and training groups). After 6 weeks of interval training for the training group and rest for the control group, 5 rats from the training group and 5 rats from the control group were removed from the test period by tissue sampling. Then, the remaining 10 rats of the training group entered the two- and three-week taper period and 10 rats of the control group were placed in two and three-week control groups. Progressive interval training was performed in 6 sessions, 30 minutes each session at a speed of 15 to70 meters per minute. Then, a taper phase for three weeks in decreasing intensity pattern was performed. An analysis is done with one-way ANOVA and Tukey test at P<0.05.

Immuno histochemical study of lung tissue from different groups showed that interval training causes the significant increase in the expression of caspase-3 in young rats (p≤0.001). While taper training could reduce caspase-3 expression levels in pneumocytes in the lung tissue. Three - week taper versus two weeks taper showed a significant decrease in the expression of caspase-3 in the type I pneumocytes (p≤0.033) and type II pneumocytes (p≤0.001).

The results of this study show that the use of a period of training load reduction can be investigated as an appropriate method to reduce apoptosis in the pulmonary alveoli after intense exercise, and this investigation can be considered to improve the Lung physiology indicators in human samplesproblems.