The protective effect of ischemic preconditioning on rat testis

BACKGROUND It has been demonstrated that brief episodes of sublethal ischemia-reperfusion, so-called ischemic preconditioning, provide powerful tissue protection in different tissues such as heart, brain, skeletal muscle, lung, liver, intestine, kidney, retina, and endothelial cells. Although a recent study has claimed that there are no protective effects of ischemic preconditioning in rat testis, the protective effects of ischemic preconditioning on testicular tissue have not been investigated adequately. The present study was thus planned to investigate whether ischemic preconditioning has a protective effect on testicular tissue. METHODS Rats were divided into seven groups that each contained seven rats. In group 1 (control group), only unilateral testicular ischemia was performed by creating a testicular torsion by a 720 degree clockwise rotation for 180 min. In group 2, group 3, group 4, group 5, group 6, and group 7, unilateral testicular ischemia was performed for 180 min following different periods of ischemic preconditioning. The ischemic preconditioning periods were as follows: 10 minutes of ischemia with 10 minutes of reperfusion in group 2; 20 minutes of ischemia with 10 minutes of reperfusion in group 3; 30 minutes of ischemia with 10 minutes of reperfusion in group 4; multiple preconditioning periods were used (3 x 10 min early phase transient ischemia with 10 min reperfusion in all episodes) in group 5; multiple preconditioning periods were used (5, 10, and 15 min early phase transient ischemia with 10 min reperfusion in all episodes) in group 6; and, multiple preconditioning periods were used (10, 20, and 30 min early phase transient ischemia with 10 min reperfusion in all episodes) in group 7. After the ischemic protocols were carried out, animals were sacrificed by cervical dislocation and testicular tissue samples were taken for biochemical measurements (protein, malondialdehyde, nitric oxide) and histological examination. RESULTS Although decreased tissue malondialdehyde levels were detected in the groups of 2, 3, 4, and 5 compared to group 1, significant decreases were observed in only group 2 and group 5 (p < .05). Nitric oxide levels were numerically decreased in all groups compared to the control group but was statistically significant only in group 5 (p < .05). Histopathological examination demonstrated that all groups subjected to ischemic preconditioning had less tissue damage than group 1 (p < .05). CONCLUSION These results suggest that ischemic preconditioning provides tissue protection in testicular tissue.