Germ cell degeneration in the contralateral testis of the guinea pig with unilateral torsion of the spermatic cord. Quantitative and ultrastructural studies

This study evaluated the long term effects of unilateral torsion of the spermatic cord on the contralateral testis of guinea pigs, employing both fine structural and quantitative studies. Young, adult Hartley strain guinea pigs were divided into six experimental groups (12 animals per group). The first three groups consisted of 36 animals in which unilateral torsion was surgically induced. In group I (torsion maintained), unilateral torsion of the spermatic cord was maintained until the day of sacrifice; in group II (torsion and untwist), torsion of the spermatic cord was maintained for 8 to 12 hours, then the spermatic cord was untwisted and the testis was retained until the day of sacrifice. In group III (torsion and orchiectomy), testes were removed after 8 to 12 hours of spermatic cord torsion. The second three groups consisted of 36 animals: group IV (unilateral orchiectomy), group V (unilateral sham operation), and group VI (pentobarbital injection alone), which served as controls. One half of the animals from each group were killed after 4 months and the other half were killed after 8 months. The most frequently observed histologic changes in the contralateral testes of the experimental animals were focal disorganization and exfoliation of immature germ cells into the lumen. Severe damage, with almost complete absence of germ cells, was noted only in an occasional tubule. Quantitative evaluation of the germ cells of the contralateral testis revealed significant loss of germ cells in groups I, II, and III after 4 months, and in groups I and II after 8 months.(ABSTRACT TRUNCATED AT 250 WORDS)     

Acute experimental testicular torsion. No effect on the contralateral testis

Other investigators have shown that chronic unilateral testicular torsion produces negative effects on the contralateral testis in experimental animals. In the present study, bilateral testicular weight and histology, and concentrations and motility of spermatozoa from the cauda epididymidis were studied after 0 to 4 hours of acute unilateral testicular torsion in the rat. The obstruction of blood flow by torsion was documented, as well as the presence or absence of return blood flow after the relief of torsion. The above mentioned parameters of testicular function were studied at 7, 30, and 60 days after relief of torsion. Ipsilateral testis weights and epididymal sperm concentrations and motility were significantly reduced by 1, 2, and 4 hours of torsion. The histology of torsioned testes was also severely altered, and no seminiferous epithelial repair was evident 60 days after torsion. Contralateral testicles were not affected by ipsilateral torsion of 1, 2, or 4 hours duration, despite the fact that the ipsilateral testis function was completely compromised by 2 and 4 hours of torsion. These results indicate that there would be no clinical benefit in removing the acutely torsioned testis of Sprague-Dawley rats since it poses no threat to the contralateral testis.     

Quantitative evaluation of testicular biopsies from men with unilateral torsion of spermatic cord

Torsion of the spermatic cord is not uncommon among young men. Various abnormalities in the histology of the contralateral testis have been reported due to unilateral torsion of the spermatic cord. We quantitatively estimated the germ cells from three groups of men: normal individual (Group I), men with unilateral torsion of short duration (Group II), and men with unilateral torsion of long duration or some other condition such as varicocele or intermittent torsion to the contralateral testis (Group III). No significant difference in the number of spermatogonia, spermatocytes, and spermatids of Groups I and II patients was observed. This observation indicates that there was no pre-existing morphophysiologic defect in the testis of Group II patients. Severe damage in the contralateral testis was noted in Group III patients. This indicates that if a damaged testis is retained in the body for a long time, the contralateral testis may be affected. Contralateral testis may also be affected by intermittent torsion or varicocele.     

The effects of human chorionic gonadotropin treatment on the contralateral side in unilateral testicular torsion

BACKGROUND/PURPOSE: Unilateral testicular torsion can cause histologic damage, consisting of aspermatogenesis and tubular atrophy, in the contralateral testis human chorionic gonadotropin (HCG) treatment is widely used in undescended testis, and has been shown to improve histomorphometric alterations beside the testicular descent. However, the role of HCG in testicular torsion has not been investigated before. Therefore, this experimental study was conducted to evaluate the effects of HCG treatment on contralateral testicular histology and function in unilateral testicular torsion. METHODS: Forty adult male Wistar rats were randomized into 4 groups: SHAM, SHAM+HCG, TORSION, and TORSION+HCG. Torsion was created by twisting the righ testis 720 degrees and maintained by fixing it to the scrotum. HCG treatment started 24 hours after the torsion at a dose of 100 IU/kg, twice weekly for three weeks. Left orchiectomy was performed one month after the torsion and removed testes were immersed in Bouin's fixative for histopathological evaluation. Mean seminiferous tubule diameter (MSTD) was measured and Johnsen's score was calculated. Blood samples were taken for assaying serum testosteron level. RESULTS: Unilateral testicular torsion resulted in a significant decrease in spermatogenesis and MSTD on the contralateral side. Serum testosteron level was also reduced. HCG treatment improved these parameters in the contralateral 'untwisted' testis beside the serum testosteron. CONCLUSIONS: Our data demonstrates that unilateral testicular torsion adversely effects its counterpart. HCG treatment improves contralateral histomorphometric alterations and serum testosteron in unilateral torsion.     

Spermatic cord torsion: effects of cyclosporine and prednisone on fertility and the contralateral testis in the rat

Unilateral spermatic cord torsion results in contralateral degeneration and reduced fertility in the prepubertal male rat. This study was conducted to investigate the use of immunosuppression with cyclosporine and prednisone to prevent these untoward effects. Thirty-five-day-old male rats were subjected to 720 degrees unilateral spermatic cord torsion of 9 hours duration. At the time of detorsion, animals were given a subcutaneous injection of i) cyclosporine, ii) prednisone, or iii) cyclosporine combined with prednisone. Control groups included: i) animals undergoing orchiectomy of the ipsilateral testis following the torsion period, ii) hemicastration in the absence of torsion and iii) sham surgery. Orchiectomy at the end of the torsion period prevented the torsion induced reduction of fertility, contralateral seminiferous tubule diameter and testis weight. Treatment with cyclosporine combined with prednisone significantly increased these parameters above detorsion alone. These data indicate that short term immunosuppression with cyclosporine alone or in combination with prednisone limits the adverse effects of unilateral spermatic cord torsion as does removal of the damaged organ at the end of the torsion period.     

Experimental testicular torsion: Effect on endocrine and exocrine function and contralateral testicular histology

Summary In order to investigate whether unilateral testicular torsion exerts a negative influence on the previously undisturbed contralateral side, exocrine and endocrine testicular function were evaluated before and two months after torsion. A rat model with 6 hours', 12 hours' or permanent extravaginal 540° torsion of the right testis was used; a sham operated group of animals served as controls. Ejaculates were collected by electrostimulation; LH, FSH and testosterone serum levels were determined by radioimmunoassays. Eight weeks after torsion sperm output had decreased by half in the experimental groups, and LH levels increased significantly, whereas the other hormone levels, as well as the controls, remained unchanged. Morphometry of the contralateral testis revealed no alterations except a significant increase of the Leydig cells and interstitial cells in some subgroups. All observed changes correlate with the functional loss of one testis; definite evidence for contralateral damage was not observed.     

一侧睾丸扭转对对侧睾丸组织发育的影响

目的:研究一侧睾丸扭转以后对对侧睾丸组织的影响。方法:以大鼠为研究对象,按扭转时间及药物应用情况进行分组。在一侧睾丸扭转以后2个月,观察对侧睾丸曲细精管的变化。结果:一侧睾丸扭转2h以内,对侧睾丸曲细精管管腔和生精上皮增生;扭转6 h以后,曲细精管管腔和生精上皮萎缩;扭转6h以内应用别嘌呤醇能缓解对侧病变。结论:一侧睾丸扭转可以使对侧睾丸组织发育发生病理改变。     

On unilateral testicular and epididymal torsion: no effect on the contralateral testis

It is often stated that unilateral testicular torsion results in damage to the contralateral testis; however, there are a growing number of experimental and clinical papers which suggest this is not so. Conflicting results from experimental studies confuse the issue and may be due, among other things, to some specifics of the experimental model. In the present paper, we have examined bilateral rat testes 30 and 60 days after 720 degrees torsion to determine 1) the effect of unilateral testicular torsion with and without the inclusion of epididymal torsion, 2) the effect of relatively chronic torsion (24 hr., 10 day) versus relatively acute torsion (two hr., four hr.), and 3) the effect of establishing the model using scrotal surgery versus using an abdominal approach. Bilateral testicular histology, testis wt. (gm.), cauda epididymal sperm concentrations (sp./ml.), and cauda sperm motility scores (0-4) were examined. Ipsilateral testicular torsion or testicular plus epididymal torsion of two hr. or four hr. duration significantly reduced (p less than .05) ipsilateral testis weights, sperm concentrations, and motility scores, and disrupted normal tissue histology. Contralateral testicles were not altered. Epididymal ischemia alone produced no significant ipsilateral or contralateral effects. Chronic torsion (one day, 10 days) also destroyed ipsilateral testis function without altering the contralateral testicles. The occult cryptorchidism associated with the scrotal approach to establishing the torsion model had no effect on contralateral testicles. In no group, using either Lewis rats or Sprague-Dawley rats, were contralateral testicles altered by unilateral testicular torsion. These results plus recent clinical reports indicate that contralateral testicular damage due to ipsilateral torsion is hardly a proven phenomenon, let alone a significant factor contributing to male infertility.     

Flow cytometric DNA analysis demonstrates contralateral testicular deterioration in experimental unilateral testicular torsion of prepubertal rats

Summary. It has been postulated that unilateral testicular torsion causes damage to the contralateral testis and reduces fertility. However, in animal studies such an effect has not been fully proven by histopathologic examination or other conventional assays of spermatogenesis. We investigated the effect of unilateral testicular torsion on contralateral spermatogenesis in prepubertal rats using quantitative flow cytometric DNA analysis. Male rats were divided into three groups which underwent sham-operation, simple hemiorchiectomy or unilateral testicular torsion. Five weeks after these operations, fertility and spermatogenesis by flow cytometry were evaluated. No significant differences were observed in body weight, contralateral testicular weight or serum testosterone concentration among the three experimental groups. In the torsion group, mean seminiferous tubular diameter, number of foetuses, fertility rate and percentage of haploid cells were all significantly decreased compared to the other two groups. These results suggest that unilateral testicular torsion causes damage to the contralateral testis and consequently can reduce the future fertility of prepubertal rats.     

New animal model to evaluate testicular blood flow during testicular torsion.

BACKGROUND/PURPOSE: Unilateral testicular torsion is known to cause infertility because of damage to the contralateral testis. Testicular damage has been attributed to many different mechanisms, one of which is altered contralateral blood flow. In our experiment, in an effort to identify the reason for contralateral testicular injury, the authors developed an accurate method of measuring blood flow in both testes before, during, and after unilateral torsion. METHODS: Four- to 6-week-old piglets weighing 4 to 6 kg were studied. The animals were anesthetized, intubated, ventilated, and catheterized for vascular access. Piglets were assigned randomly to a sham group or a group undergoing 360 degrees or 720 degrees torsion of the left testis (n = 5 per group) for 8 hours, after which it was untwisted. Data were collected at baseline (T = 0), 8 hours of torsion (T = 8), and 1 hour after detorsion (T = 9). Mean arterial blood pressure and heart rate were monitored continuously. Testicular blood flow was determined using radiolabeled microspheres. Blood flow data were evaluated by analysis of variance. RESULTS: In the 360 degrees torsion group, blood flow changes were insignificant during torsion and after detorsion. In the 720 degrees torsion group, blood flow to the twisted testis was reduced significantly, whereas the contralateral testis was unaffected. One hour after detorsion, blood flow to both testes was increased significantly. CONCLUSIONS: The authors describe a new animal model to evaluate testicular blood flow during and after testicular torsion. Increased blood flow after detorsion may be the cause of testicular damage in patients with unilateral testicular torsion.     

Clinical study of unilateral intravaginal testicular torsion and anatomicalcomparative study of bilateral testes in orchiopexy

Fourty-eight patients were operated on for unilateral intravaginal testicular torsion at Yokohama Red Cross Hospital during the period between July 1976 and December 2001. Orchiopexy was carried out on 20 out of 48 patients. Only 8 patients could receive orchiopexy within 8 hours after the onset of symptoms. Although, 24 of the 48 patients had visited a medical doctor within 8 hours after the onset. Therefore, the less the testes might be sacrificed if these patients could be immediately sent to a clinic with an urologic speciality. The contralateral uninvolved testis has been said to require orchiopexy because it has an anatomical structure similar to the testis with torsion. However, the contralateral testes in 5 out of 20 patients with ipsilateral orchiopexy turned out to have a normal anatomical structure according to our classification of intravaginal testicular torsion. This suggests that no orchiopexy is necessary if the contralateral uninvolved testis has a normal anatomical structure from the standpoint of torsion type.     

Effect of unilateral testicular torsion on blood flow and histology of contralateral testes.

BACKGROUND/PURPOSE: Infertility occurs in 25% of patients after unilateral testicular torsion; hence, the authors examined hemodynamic and histological changes in both testes after acute testicular torsion in neonatal piglets. METHODS: The animals were anesthetized, intubated, ventilated, catheterized, and assigned randomly to a sham group or one of three experimental groups undergoing 720 degrees torsion of the left testis for 8 hours after which it was untwisted in group I and removed in group II. In group III, both testes were removed. Data were collected at baseline (T = 0), 4 hours (T = 4), and 8 hours of torsion (T = 8) and at the ninth hour of the experiment (T = 9). Testicular blood flow was determined by using radiolabeled microspheres. The testes also were examined blindly with routine and electron microscopy. RESULTS: In group I, testicular blood flow decreased in the affected testis during torsion and increased significantly after detorsion, whereas blood flow to the contralateral testis increased significantly after detorsion. Sham-operated animals showed no histological abnormality in either testis. In all torsion groups, the affected testis showed extensive changes caused by hemorrhagic necrosis. The contralateral testis only showed changes in group I. CONCLUSION: Unilateral testicular torsion resulted in ipsilateral damage caused by a decrease and subsequent increase in blood flow while in the contralateral testis; damage was the result of a significant increase in blood flow after detorsion.     

Activation of endothelial nitric oxide synthase in contralateral testis during unilateral testicular torsion in rats

There are controversies about the injury of the contralateral testis during unilateral testicular torsion (UTT). An autonomic reflex arc between bilateral testes has been proposed. The authors focused on the involvement of nitric oxide (NO) in the contralateral testis during UTT. Eight-week-old male Wistar rats underwent unilateral torsion (1 h)-detorsion (up to 24 h). NO synthase (NOS) activity was detected as NADPH-diaphorase activity after fixation by paraformaldehyde. N-nitro-L-Arginine methyl ester (L-NAME, 20 mg/kg) was injected intravenously to the other group of rats. To evaluate the testicular injury, proteolysis of alpha-fodrin production was detected by Western blotting. Apoptosis of the germ cells was evaluated by TUNEL. Long-term effect on spermatogenesis was evaluated by flow cytometry at 60 days after UTT. Transient activation of NOS was detected following the proteolysis of alpha-fodrin in the contralateral testis. L-NAME inhibited these alterations. NADPH-diaphorase activity and eNOS immunoreactivity were co-localized in the endothelial cells. These reactions were not observed in other organs. There was neither enhanced apoptosis nor deteriorated spermatogenesis in the contralateral testis during and 60 days after UTT. In the contralateral testis, eNOS-derived NO regulates the vasomotor function against unilateral testicular torsion, whereas it acts slightly cytotoxic. These results suggest the possible involvement of a testis-specific neurovasomotor reflex between the bilateral testes.     

Experimental torsion of the spermatic cord. Histological and histochemical studies (author's transl)

In 40 male adult rats on unilateral torsion of the spermatic cord was initiated by operation. In the first group (4 x 5 animals) the testes were removed after 3, 6, 12, 24 hours. The treatment of the animals in the second group (4 x 5 animals) was untwisting of the torsion after 3, 6 12, 24 hours. Three months later both testes were removed. Histological and enzymehistochemical results are as follows: 1. The extend of acute damage to the affected testis depends on the length the torsion lasted. 2. The delay of time of untwisting the testis probably does not influence the degree of later regeneration. 3. Even short duration of torsion of the affected testis results in damage to the contralateral testies.     

Blood perfusion of the contralateral testis evaluated with contrast-enhanced ultrasound in rabbits with unilateral testicular torsion

The changes of blood perfusion of contralateral testis after unilateral testicular torsion remain controversial. In this study, 28 New Zealand white male rabbits were randomly divided into five groups. Group A (n = 8), the control group, underwent a sham operation on the unilateral testis without inducing testicular torsion. In groups B, C, and D (n = 5 each), unilateral testicular torsion was induced, and, after 3, 6 or 24 h, respectively, detorsion was performed. In group E (n = 5), permanent unilateral testicular torsion was applied. Contrast-enhanced ultrasound was used to observe the blood perfusion of the contralateral testis at the following stages: pre-torsion (preopration), immediately post-torsion (postopration), pre-detorsion, immediately post-detorsion, and late-stage post-detorsion (6–12 h post-detorsion in groups B–D) or at a similar time point (15–21 h post-torsion in group E). Time-intensity curves were generated, and the following parameters were derived and analyzed: arrival time, time to peak intensity, peak intensity, and half-time of the descending peak intensity. The analysis revealed that blood perfusion of the contralateral testis increased immediately after testicular torsion on the opposite side (P < 0.05), which increased with prolonged testicular torsion of the other testis. This research demonstrated that contrast-enhanced ultrasound was valuable in evaluating blood perfusion of the contralateral testis after unilateral testicular torsion.     

Protective role of erythropoietin during testicular torsion of the rats

Testicular torsion is an important clinical urgency. Similar mechanisms occurred after detorsion of the affected testis as in the ischemia reperfusion (I/R) damage. This study was designed to investigate the effects of erythropoietin (EPO) treatment after unilateral testicular torsion. Fifty male Sprague-Dawley rats were divided into five groups. Group 1 underwent a sham operation of the right testis under general anesthesia. Group 2 was same as sham, and EPO (3,000 IU/kg) infused i.p., group 3 underwent a similar operation but the right testis was rotated 720° clockwise for 1 h, maintained by fixing the testis to the scrotum, and saline infused during the procedure. Group 4 underwent similar torsion but EPO was infused half an hour before the detorsion procedure, and in group 5, EPO was infused after detorsion procedure. Four hours after detorsion, ipsilateral and contralateral testes were taken out for evaluation. Treatment with EPO improved testicular structures in the ipsilateral testis but improvement was less in the contralateral testis histologically, but EPO treatment decreased germ cell apoptosis in both testes following testicular IR. TNF-α, IL-1β, IL-6 and nitrite levels decreased after EPO treatment especially in the ipsilateral testis. We conclude that testicular I/R causes an increase in germ cell apoptosis both in the ipsilateral and contralateral testes. Eryhropoietin has antiapoptotic and anti-inflammatory effects following testicular torsion.     

Late changes of the testicular tissue in experimental torsion of the spermatic cord (author's transl)

In three experimental groups and a control group unilateral or bilateral torsion of the testicle were carried out in 195 mature rats. The testicles were retorted at various intervals up to 24 hours. Four weeks and three months following the torsion the retorted as well as the contralateral normal testicles were examined morphologically and histologically. A total testicular torsion is fully reversable after one hour in all cases and after 2 hours in 40% of the cases. The Sertoli cells are destroyed after 6 hours and the Leydig cells after 10 hours. The time causing irreversable tissue damage therefore appears to be shorter than generally assumed, and the germinative epithelium is reacting faster than the testosterone producing Leydig cells. No changes were noted in the contralateral normal testis.     

Valoration of the FAS in the contralateral testis after unilateral testicular torsion. Experimental study in rats

The role the FAS and BCL-2 in the apoptosis of testicular cells in the contralateral testis after unilateral testicular torsion, was investigated. We compared with control group. These experiments were performed in male Wistar rats prepuberal old. FAS and BCL-2 determination is realized in cells cultures of contralateral testis. Flow cytometry and immunohistochemistry studies, using a FAS and BCL-2 specific monoclonal antibody, were utilized to value FAS y BCL-2 expression on testiculaires cells following unilateral testicular torsion. We observed an increase of expression of FAS and decrease of BCL-2 in the contralateral testis in comparison with control group. The present results may indicate that the expression of this molecules is implicated in cellular apoptosis.     

Effects of unilateral testicular torsion on the blood flow of contralateral testis--an experimental study on dogs

The effects of unilateral testicular torsion on the blood flow of the contralateral testis were investigated. Fourteen adult male dogs were recruited. Seven dogs underwent unilateral testicular torsion of 4 h duration, and the other seven dogs had a control operation. Testicular blood flow was determined by colour Doppler ultrasonography before and after the testicular torsion. Bilateral orchidectomy was performed at the end of the study and histopathological changes were evaluated. Values of peak systolic velocity, end diastolic velocity, and resistive index were not statistically significant between ipsilateral and contralateral testes in the study group (p > 0.05). On comparison with the control group, blood flow in the contralateral testes showed no statistically significant difference (p > 0.05). Oedema and congestion were seen on ipsilateral testes in the study group. No histopathological changes were noted on the contralateral testes. Minimal oedema and congestion secondary to manipulation were found in the control operation testes. We conclude that unilateral testicular torsion does not decrease contralateral testicular blood flow as shown by colour Doppler ultrasonography.     

Torsion of the spermatic cord — A long term study of the contralateral testis

Summary The object of the present investigation was to study the long-term effects of the unilateral torsion of the spermatic cord on the contralateral testis. Eighteen guinea pigs were divided into 3 groups. In group I of six animals, unilateral torsion of the spermatic cords was maintained until the time of sacrifice. In group II of six animals, torsion of the spermatic cords was maintained for 8–12h, then the spermatic cords were untwisted and the animals were maintained until the day of sacrifice. Group III six animals, received an injection of pentobarbital, which served as control. All animals were sacrificed after 16 months. Extensive light and electron microscopic studies were carried out. In the contralateral testes of the experimental group of animals, several degenerative changes were noted, which included excessive intraepithelial vacuolization, a loss of germ cells and the presence of tubules containing only Sertoli cells and a few spermatogonia. 10.6% and 19.5% seminiferous tubules were damaged in the contralateral testes of torsion maintained and the torsion reversed groups of animals, respectively in comparison to 3.1% tubular damage (indicated only by occassional presence of intraepithelial vacuoles and necrotic germ cells), in the control testis. It was concluded that long-term effect of unilateral torsion of the spermatic cord is permanent and irreversible in nature.