Comparison of Blood Flow and Histological Changes in Rat Models of Testicular Ischemia

Beneficial effects of (-)-epigallocatechin gallate on ischemia-reperfusion testicular injury in rats

BACKGROUND/PURPOSE

The purpose of the study was to determine the effect of (-)-epigallocatechin gallate (EGCG) on testicular ischemia-reperfusion injury in rats.

METHODS

Forty male Wistar rats were assigned to 5 groups. A sham operation was performed on the animals in group 1. In group 2, after 4 hours of unilateral testicular ischemia, 4 hours of testicular reperfusion was performed with EGCG administered 1 hour before reperfusion. In group 3, the same surgical procedure as in group 2 was performed, but without EGCG. Serum superoxide dismutase activity, creatine kinase, and lactate dehydrogenase were then measured in blood samples from groups 1 to 3. In group 4, after 4 hours of unilateral testicular ischemia, testicular reperfusion was performed. In group 5, the same procedure as in group 4 was performed, but with EGCG administered 1 hour before reperfusion. For groups 4 and 5, bilateral orchiectomy was performed for histologic examination 4 weeks after reperfusion was started.

RESULTS

Serum superoxide dismutase activity was significantly higher in group 2 than in group 3. The ratios of bilateral testicular weight, mean seminiferous tubule diameter, and germinal epithelial cell thickness were significantly higher in group 5 than in group 4.

CONCLUSIONS

Therapy with EGCG before reperfusion might exert protective effects via antioxidant activities in a rat experimental model of testicular ischemia-reperfusion injury.

Ipsilateral testicular necrosis and atrophy after 1,080-degree torsion of the spermatic cord in rats

PURPOSE

To assess the incidence of testicular necrosis/atrophy immediately after 1 to 4 hours of 1,080-degree torsion of the spermatic cord, and 60 days after detorsion of the spermatic cord.

METHODS

42 rats were divided in 7 groups. Except for the control group, surgical torsion of the right spermatic cord was performed in all groups (T0). After 1, 2, or 4 hours of torsion, each group underwent either ipsilateral orchiectomy (groups OT1, OT2, and OT4), or detorsion of the spermatic cord and observation for 60 days (groups DT1, DT2, and DT4), before they were evaluated for the presence of testicular necrosis/atrophy.

RESULTS

Only one rat (5.5%) in groups OT1, OT2, and OT4 had testicular necrosis, in comparison with six rats (33.3%) in groups DT1, DT2, and DT4 (p=0.04). The incidence of testicular necrosis/atrophy was not different between subgroups T1, T2, and T4, and the control group (p>0.05). There was, however, a tendency toward greater incidence of necrosis/atrophy in the rats in group DT4.

CONCLUSION

The incidence of testicular necrosis/atrophy immediately after 1 to 4 hours of 1,080-degree torsion of the spermatic cord is 5.5%, in comparison with 33.3% sixty days after detorsion of the spermatic cord.

Rosuvastatin protects tissue perfusion in the experimental testicular torsion model

Recently, anti-inflammatory and tissue protective effects of statins have been shown independent from its anti-hyperlipidemic effect. It has been shown that one of the statins, rosuvastatin, may reduce ischemia/reperfusion (I/R)-induced tissue injury in the brain, intestines, and heart. We planned an experimental study to evaluate the effect of rosuvastatin on I/R injury encountered after the detorsion of the testicular torsion. Rats were divided into three groups. In group 1, testis basal blood flow (basal value) was measured with LASER Doppler flowmeter (LDF). Testis was relocated into the scrotum without torsion. Two and 3 h after the basal measurement, testis was brought out from the same incision, and the second (second value) and third (third value) testicular blood flow measurements were done, respectively. In group 2, after the measurement of basal value testicular torsion was created. Second and third value measurements were obtained with LDF at the end of the 2 h of testicular torsion just before the detorsion and 1 h after detorsion. In group 3, same procedures in torsion/detorsion group were repeated in this group, but 10 mg/kg rosuvastatin was injected intraperitoneally 30 min before detorsion. Second values in groups 2 and 3 were significantly lower than group 1. Third values were significantly low in group 2 compared to groups 1 and 3. Regarding the third measurement, there was no significant difference between the groups 1 and 3. Tissue injury is closely related with condition of microvascular perfusion after I/R. Rosuvastatin can protect tissue perfusion in the experimental testicular torsion model.

Possible mechanisms for epididymal sparing during testicular ischemia

OBJECTIVES

Although extensive research has been conducted on the normal anatomy and physiology of the epididymis, the effects of ischemia on the organ have not been primarily investigated. The aim of the present study was to investigate the macroscopic and microscopic effects of prolonged ischemia on the epididymis and the factors that may contribute to its resistance to ischemia.

METHODS

Six groups of male Sprague-Dawley rats (6 rats/group) were studied. Groups 1, 2, and 3 underwent a sham operation of 4, 8, and 12 hours, respectively, and groups 4, 5, and 6 underwent 4, 8, and 12 hours of ischemia, respectively. The ipsilateral testes and epididymides were monitored throughout the experiment. At the conclusion of the experiment, bilateral orchiectomy was performed, and structures were histologically evaluated.

RESULTS

There were no abnormal macroscopic findings of the bilateral epididymides of groups 1, 2, and 3 or of the contralateral, control epididymides of groups 4, 5, and 6. Macroscopically, there was a direct correlation between the length of ischemia and the degree of hemorrhagic discoloration of the proximal caput. The degree of hemorrhagic infiltration noted microscopically was consistent with the macroscopic observations. The epithelia of the ischemic epididymides remained intact with numerous microvilli.

CONCLUSIONS

The results of this study suggest that the epithelium of the epididymis is relatively resistant to ischemic damage compared with the gonad during testicular ischemia.

Surfactant administration reduces testicular ischemia-reperfusion injury

PURPOSE

The mechanism of testicular ischemia-reperfusion injury has not been well delineated. We determined the efficacy of a biocompatible surfactant (tetronic 1107) to reduce tissue injury and evaluated cell membrane integrity as reflected by calcium ion permeability in an in vivo animal model of testicular ischemia-reperfusion.

MATERIALS AND METHODS

Three groups of male Sprague-Dawley rats (6 per group) were studied. Group 1 was the nonoperative control, and groups 2 and 3 underwent 4 hours of unilateral testicular ischemia followed by 4 hours of reperfusion. Ten minutes after reperfusion 0.4 ml. saline was administered intravenously to group 2 and 180 mg./kg. surfactant tetronic 1107 to group 3. 99mTechnetium pyrophosphate was used to monitor calcium ion uptake by the ipsilateral and contralateral testicles. Both testicles were also examined histologically.

RESULTS

The surfactant treated animals had markedly diminished hemorrhagic discoloration and vascular congestion compared to saline treated animals. These results were confirmed microscopically with improved nuclear chromicity and disarray of germ cell layers of the seminiferous tubules. The surfactant treated group also had a statistically significant (p <0.05) reduction in radiotracer uptake compared to the saline treated animals, confirming a reduction in calcium ion permeability.

CONCLUSIONS

The results of this study suggest that tetronic 1107 is effective in reducing tissue damage in a testicular ischemia-reperfusion animal model.