Exocrine and endocrine functions in unilateral testicular disease

Summary Exocrine testicular function was determined in 30 prepubertal and pubertal patients who had undergone detorsion and fixation for unilateral torsion of the testis, in 46 men who had undergone unilateral orchidopexy, and in 16 patients with unilateral absence of the testis. In 42 patients with seminomas and non-seminomatous testicular tumors, sperm analyses were performed before orchiectomy. The semen analyses in patients with unilateral cryptorchidism were normal in 13, doubtful in 23 and pathological in 10. The semen quality in patients with torsion was normal in 15, doubtful in 3 and pathological in 12. Of the 16 patients with monorchidism, 14 had normal sperm analyses. Of the 42 patients with seminomas and non-seminomatous testicular tumors, only two patients with HCG-negative seminomas had normal sperm analyses before orchiectomy. In patients with doubtful and pathological sperm analyses after testicular torsion and unilateral orchidopexy, elevated follicle-stimulating-hormone levels were observed. HCG-positive testicular tumors showed decreased FSH levels but elevated 17--estradiol and prolactin levels.Supported by the Fonds zur Förderung der wissenschaftlichen Forschung, Austria, P 4030     

Semen quality and endocrine parameters after acute testicular torsion.

Of 16 postpubertal patients evaluated following testicular torsion 9 were treated with detorsion and bilateral orchiopexy (detorsion group), and 7 were treated with ipsilateral orchiectomy and contralateral orchiopexy (orchiectomy group). Each patient was evaluated with regard to semen quality, endocrine parameters (follicle-stimulating hormone, luteinizing hormone and testosterone) and the presence or absence of semen antisperm antibodies. These data were compared to similar data from a group of proved fertile semen donors. The semen quality in the detorsion group did not differ significantly from that of controls (p = 0.25) but follicle-stimulating hormone was significantly elevated compared with that of controls before and after stimulation with gonadotropin-releasing hormone. The orchiectomy group, which had been subjected to prolonged torsion (mean 69 hours), demonstrated a significant decrease in semen quality compared with semen quality in controls (p = 0.001), with average sperm density of only 29.0 million per ml. Baseline and post-stimulation levels of follicle-stimulating hormone in the orchiectomy group were also significantly abnormal when compared with those in controls and in the detorsion group. Our study demonstrates that testicular damage (changes in semen quality and/or endocrine parameters) occurs in the ipsilateral and contralateral testis following torsion, regardless of treatment modality. However, with early intervention by detorsion and testicular salvage, subsequent semen quality is likely to remain within normal limits. Late surgical intervention, even with removal of the nonviable testes, may result in significant impairment of semen quality.     

Gonadal dysfunction after testicular torsion: luteinizing hormone and follicle-stimulating hormone response to gonadotropin releasing hormone

We studied 14 postpubertal patients at an average of 33 months after treatment for testicular torsion. Of these patients 11 had been treated by detorsion and 3 by orchiectomy. Five normal male volunteers of the approximate age of the study group served as controls. The patients treated by detorsion were subdivided into 3 groups based on the degree of atrophy of the detorsed testicle: group 1--no testicular atrophy (5), group 2--25 per cent testicular atrophy (2) and group 3--greater than 90 per cent testicular atrophy (4). Mean duration of torsion was greatest in the orchiectomy group (161 hours) compared to 6, 16 and 29 hours for groups 1, 2 and 3, respectively. The serum luteinizing hormone and follicle-stimulating hormone response to an intravenous bolus of 100 mcg. synthetic gonadotropin releasing hormone was measured in all patients. All groups had a greater mean follicle-stimulating hormone response to gonadotropin releasing hormone stimulation than controls (p less than 0.05). Patients who underwent orchiectomy had the greatest follicle-stimulating hormone response to gonadotropin releasing hormone stimulation. Mean luteinizing hormone response to gonadotropin releasing hormone stimulation was normal in patients without atrophy (group 1) but it was greater than controls in patients who had atrophy (groups 2 and 3) or who underwent orchiectomy (p less than 0.05). Several conclusions could be made from our study. All patient groups treated for torsion had evidence of testicular dysfunction. Patients who underwent orchiectomy displayed more testicular dysfunction than patients who had atrophy after detorsion. Testicular dysfunction after torsion is more likely to involve spermatogenic before Leydig cell function.     

Late results after surgical treatment of maldescended testes with special regard to exocrine and endocrine testicular function

Testicular volumes and exocrine testicular function were determined in 82 men who had undergone orchidopexy (36 bilateral, 46 unilateral) at 5-18 years of age. The testicular volumes in unilateral and bilateral orchdopexied patients correspond to those on normal mature males. Semen analyses in unilateral cryptorchidism were normal in 13, doubtful in 23 and pathological in 10 patients. Out of a total of 36 patients who have undergone bilateral orchidopexy, 3 patients were found to have normal, 7 patients doubtful and 26 patients pathological sperm analyses. Endocrine evaluation in bilateral cryptorchidism (prepuberal, puberal and postpuberal) showed no differences in testosterone levels compared to control groups. Some postpuberal patients with pathological sperm analyses were found to have elevated LH and FSH levels; 22 postpuberal patients with pathological sperm analyses showed hypergonadotropism with markedly elevated LH and FSH levels after GnRH.     

Pentoxifylline improves blood flow to both testes in testicular torsion

Objectives: Electromagnetic and radioisotopic studies have shown thatunilateral testicular torsion causes a decrease in contralateral testicularblood flow. Pentoxifylline improves microvascular blood flow in conditionsof vascular insufficiency. An experimental study was designed to evaluatethe effects of pentoxifylline (Ptx) on blood flow to both testes duringunilateral testicular torsion and detorsion.Materials and methods: Thirty-six adult male albino Wistar rats wererandomly divided into six groups where each consisted of six rats: group1: sham operation, group 2: sham operation with Ptx, group 3: torsion,group 4: torsion with Ptx, group 5: detorsion, group 6: detorsion with Ptx.After intraperitoneal administration of Ptx at a dose of 50 mg/kg 15minutes before torsion; right testes of the rats underwent 30 minutes oftorsion and 30 minutes of detorsion. Blood flows of both testes weremeasured during torsion and detorsion simultaneously by using ¹³³Xeclearance technique.Results: Unilateral testicular torsion caused decrease in bilateraltesticular blood flow. Pentoxifylline had no effect on testicular blood flowduring torsion. Detorsion caused a partially increase in blood flow toipsilateral (detorted) testis, but had no effect on contralateral (nontorted)testicular blood flow. Pentoxifylline administration during detorsionsignificantly increased blood flow to both testes.Conclusions: Testicular torsion is a pathological process that causesdecreased blood flow to both testes. Pentoxifylline improves blood flow toboth testes during detorsion in a rat model of testicular torsion. Furtherstudies are needed to evaluate the effects of pentoxifylline on testiculartorsion.     

青春期精索扭转的诊治分析(附67例报告)

目的:提高精索扭转的早期诊断和治疗水平,减少睾丸丧失。方法:回顾性分析2003年8月~2011年12月收治的67例青春期精索扭转的临床资料:患者年龄13~16岁,平均14.6岁。发病6小时内就诊23例,6~24小时39例,24小时以上5例。本组彩超检查53例;手术治疗63例,非手术治疗4例。并分析其确诊、误诊及睾丸挽救率。结果:首诊确诊率72%(48/67),误诊率28%(19/67)。误诊病种包括附睾-睾丸炎52%(10/19),鞘膜积液16%(3/19),腹股沟疝16%(3/19),输尿管结石11%(2/19),睾丸血肿5%(1/19)。67例中,外科干预63例,均为鞘膜内360°~1 080°扭转,其中发病6小时内手术探查19例,睾丸挽救率84%(16/19);6小时以上手术探查44例,睾丸挽救率23%(10/44),两组间差异有统计学意义(P0.05,两组睾丸中位扭转角度540°)。挽救及健侧睾丸行阴囊肉膜下固定术。切除睾丸病理检查结果为出血坏死性改变。非手术治疗4例中,2例手法复位成功,1例就诊睾丸已萎缩,1例自发缓解。挽救睾丸26例,其中16例随访6~18个月,睾丸萎缩11例。结论:精索扭转误诊率较高,青春期突发阴囊剧痛首先要考虑精索扭转的可能。彩超为一线检查方法。扭转程度及缺血时间是影响睾丸结局的重要因素,及时手术探查可降低睾丸切除率。因此,早期确诊和治疗是避免睾丸丧失的关键。     

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.     

Beneficial effects of rolipram,a phosphodiesterase 4 specific inhibitor,on testicular torsion-detorsion injury in rats

IntroductionThe aim of the study is to investigate the effect of Rolipram, a selective phosphodiesterase 4 inhibitor, on testicular torsion – detorsion injury.MethodsSixty young male rats were divided into five groups. In each group, the right testes of six rats were removed four hours after detorsion for biochemical analysis, and the right testes of the remaining six rats were removed 24 h after detorsion for pathological analysis. In group 1 (sham-operated) right orchiectomy was performed without torsion, and right testes were sent to the laboratory for biochemical and pathologic analyses. In group 2 (control) torsion was applied to the right testes for 60 min, and detorsion was performed without the administration of Rolipram. In group 3 torsion was applied to the right testes for 60 min. 1 mg/kg Rolipram was administered 30 min before detorsion. In group 4 torsion was applied to the right testes for 60 min, and 1 mg/kg Rolipram was administered during detorsion. In group 5 torsion was applied to the right testes for 60 min. 1 mg/kg Rolipram was administered 30 min after detorsion. The malondialdehyde and nitric oxide levels were determined. The rates of necrosis and apoptosis were evaluated by histopathological examination.ResultsThe level of malondialdehyde was higher in the torsioned groups (Group 2, 3, 4, 5) than that in group 1 (p = 0.004). There was no statistically significant difference between the groups regarding the level of nitric oxide (p = 0.182). Apoptosis was higher in groups 2, 3 and 4 than in group 1; however, apoptosis was similar in group 1 and group 5 (p = 0.122). The level of necrosis in group 1 was similar to that in groups 4 and 5 (p = 0.194 and p = 0.847, respectively).ConclusionWe suggest that the administration of Rolipram can decrease the rate of necrosis and apoptosis in testicular ischaemia-reperfusion injury.     

An enigma: Contralateral effects of experimental unilateral testicular torsion

To investigate the effects of unilateral testicular torsion on both testes, we studied 4 groups of adult male New Zealand rabbits using sham operation, torsion and detorsion after one or eight hours and permanent torsion. Bilateral orchiectomy was performed 9 weeks after the operation, and testicular weights, Johnsen scores, quantitative analyses, tubular diameters were calculated and histopathologic diagnosis was determined. Testicular weights, Johnsen scores, spermatid counts and tubular diameters were all decreased in torsioned testes depending on the duration of torsion. The contralateral testes showed no significant change in any of the study groups when compared with the control group.     

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.     

Les torsions du cordon spermatique chez l’enfant

Objectives

To evaluate the frequency of testicular torsion, to describe its clinical presentation and treatment and to evaluate the treatment results at Tokoin University Hospital, Lomé, Togo.

Patients and Methods

This is a retrospective study of the files of 17 patients seen in the pediatric surgery department in the period 1 January 2002 to 31 December 2006 with testicular torsion diagnosed at surgery. The following parameters were studied: patient age, delay prior to presentation, symptoms, diagnostic investigations, treatment and post-operative results.

Results

During the study period, 57 patients with acute scrotum were treated in the department of pediatric surgery. Testicular torsion was found in 17 (29.8%) with 11 patients being aged between 6 and 15 years, showing a clear preponderance of boys in puberty. The mean age of our patients was 9 years (range 7 days to 15 years). The average duration of symptoms prior to presentation was 30 hours (range 10 to 72 hours). Pain was the main symptom in infants and older children. Eleven of 17 patients underwent colour Doppler sonography. Surgical interventions consisted of surgical exploration followed by detorsion of the cord and bilateral fixation of the testes. All 17 testes were preserved. With an average follow-up of 12 months (range: 4 months to 5 years) the post-operative period was uneventful.

Conclusion

Testicular torsion mainly occurs in the neonatal period and during puberty. However, it may also occur between these two periods. Surgical exploration is mandatory in every suspected case of spermatic cord torsion.     

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.     

睾丸扭转的诊治分析(附20例报告)

目的 提高睾丸扭转的诊断和治疗水平.方法 回顾性分析本院2004年10月～2010年7月诊治的20例睾丸扭转患者的临床资料.平均年龄22.1(15～30)岁,发病至确诊的时间4h～3个月,平均7.4天.9例发病于睡眠中,18例以突发睾丸剧烈疼痛起病,15例提睾反射消失,10例阴囊抬高试验(Prehn征)阳性,7例睾丸横...     

睾丸扭转的诊治(附59例报告)

目的 探讨睾丸扭转的诊治。方法 回顾性分析59例睾丸扭转患者的临床资料。结果 1例为腹腔内恶变隐睾扭转，余58例（59次）发病时中位年龄18．5岁，均无发热，50例次在夜间或剧烈运动后发病。4例手法复位成功。1例手法复位后再次扭转，拒行手术致睾丸萎缩。2例明确睾丸已坏死未手术治疗，患睾逐渐萎缩。接受手术探查的52例中有15例睾 丸存活，其中发病超过24d的1例，不到10h11例。结论 青少年夜间或运动后突发急性睾丸痛应该警惕扭转的可能，必要时紧急手术探查，手法复位可尝试应用。     

Late hormonal levels, semen parameters, and presence of antisperm antibodies in patients treated for testicular torsion

In spite of prompt diagnosis and either orchiectomy or preservation of the affected testis, infertility remains a significant sequel to testicular torsion. The objective of this study was to evaluate the late endocrine profile, seminal parameters, and antisperm antibody levels after testicular torsion. We also analyzed the impact of orchiectomy or detorsion on the organ fate. Of 24 patients evaluated after testicular torsion, 15 were treated with orchiectomy (group 1) and 9 were treated with orchiopexy (group 2). All subjects were assessed by semen analysis, endocrine profile (levels of follicle-stimulating hormone, luteinizing hormone, and testosterone), and seminal antisperm antibody levels. A group of 20 proven fertile men was used as the control. Median ischemia time in group 1 (48 hours) was significantly higher than in group 2 (7 hours). Both groups demonstrated decreases in sperm count and morphology compared with controls. Group 1 showed a significantly higher motility than group 2 (P = .02). Group 1 also showed a significantly better morphology by World Health Organization and Kruger criteria than group 2 (P = .01). All patients presented endocrine profiles within the normal range, and no significant differences in antisperm antibody levels were detected between the groups. However, a trend for higher levels was found in patients treated for testicular torsion, regardless of the fate of the testis. Moreover, no significant correlation was found between antisperm antibody levels and age at torsion, ischemia time, seminal parameters, or treatment applied. In conclusion, we found that after torsion patients maintain late hormonal levels within the normal range. Testicular fate did not have any correlation with the formation of antisperm antibodies. Although sperm quality was preserved in most of the patients with the exception of sperm morphology, patients treated with orchiectomy presented better motility and morphology compared with the detorsion group. Further studies may clarify whether maintenance of a severely ischemic testicle may impair testicular function.     

Clinical study on operative treatment of acute scrotum

Between July 1986 and March 2006, 102 patients underwent an operation for acute scrotum. Median age was 12.0 years old (range 0-51). Post-operative diagnosis revealed 50 cases (49%) of spermatic cord torsion, 29 cases (28%) of epididymal appendix torsion, and 13 cases (13%) of acute epididymitis. Spermatic cord torsion was most frequent in the age between 0 and 5, and 11 and 20, while epididymal appendix torsion was most frequent between 6 and 10. Moreover, acute epididymitis was most frequently seen in the age over 20. There were no apparent differences in the clinical symptoms such as scrotal pain, scrotal swelling, and abdominal pain. In the physical examinations, pyuria was the only finding to indicate acute epididymitis. In case of spermatic cord torsion, 'golden time' is defined as the time from onset to operation when testicular function can be expected for preservation. In this study golden time was defined as 8 hours because the testes was preserved in all 23 patients receiving the operation within 8 hours, but in only 10 (37%) out of 27 patients receiving the operation after 8 hours. Moreover, the operation within 24 hours saved the testes in approximately 90% of the patients. In patients with acute scrotum, emergency operation should be performed as speedily as possible for preservation of testicular function.     

睾丸扭转的早期诊断和治疗

目的 提高睾丸扭转的早期诊治水平.方法 回顾性分析本院2001年4月至2011年5月得到早期诊断和治疗的12例睾丸扭转患者的临床资料.平均年龄21(14～28)岁.发病至确诊时间2～6h,平均4.5h..12例发病时均有睾丸剧烈疼痛症状.12例均表现患侧精索异常.12例均行彩超检查,11例显示血流消失或减少.结果 12例均在发病后10小时内手术复位.结论 早期睾丸扭转诊断应重视精索的检查,精索异常是最主要的特征,彩超是最重要的辅助检查且有诊断价值.     

Testicular torsion: direction,degree, duration and disinformation

PURPOSE: We reviewed and contrast with the literature the cumulative clinical experience at our pediatric urological division in the last 20 years with managing testicular torsion, focusing specifically on the direction and degree of testicular torsion and the duration of symptoms before presentation. We also addressed the incidence of gastrointestinal symptoms, role of manual detorsion, residual torsion and incidence of atrophy. MATERIALS AND METHODS: We reviewed the medical records of 200 consecutive males 18 months to 20 years old who underwent surgical exploration by a pediatric urologist for a diagnosis of testicular torsion between 1980 and 2000. RESULTS: Of 186 nonelective explorations symptoms were localized to the left side in 52% and to the right side in 48%. Information on the direction and degree of testicular rotation was available in 162 of 186 cases (87%) and anticipated medial rotation occurred in only 108 (67%). Lateral rotation in 54 of 162 cases (33%) occurred in 28 of 84 (33%) with left torsion and in 26 of 78 (33%) with right torsion. A median of 540 degrees of torsion (range 180 to 1,080) was noted in the 70 orchiectomy cases (38%) and a median of 360 degrees (range 180 to 1,080) was noted in the 116 salvaged testes (62%). Manual detorsion was attempted in 53 orchiopexy cases with residual torsion in 17 (32%). Testicular atrophy developed in 27% of the patients. CONCLUSIONS: The traditional teaching that testicular torsion occurs primarily in the medial direction is misleading since in a third of cases it occurs in the lateral direction. While manual detorsion should be guided by response and return of normal anatomy, surgical exploration remains necessary since residual torsion still poses a risk to testicular viability. Long-term followup is warranted to assess the true incidence of subsequent atrophy after the management of acute testicular torsion.     

Testicular nitric oxide levels after unilateral testicular torsion/detorsion in rats pretreated with caffeic acid phenethyl ester

Nitric oxide (NO) plays an important role in modulating blood flow in normal and in several pathological conditions, and its levels seem to change with ischemia–reperfusion injuries. Caffeic acid phenethyl ester (CAPE), an active component of propolis, exhibits antioxidant properties. This experimental study was designed to determine the changes in NO levels and the effect of CAPE on NO levels after testicular torsion/detorsion in rats. Thirty-five adult male albino rats were divided into four groups: sham operation (n=8), torsion (n=9), saline/detorsion (n=9), and CAPE/detorsion (n=9). Rats in the sham operation group were killed after the testes were handled without torsion. Rats in the torsion group were killed after 720° clockwise testicular torsion for 2 h. CAPE was administered 30 min before detorsion in the CAPE/detorsion group and saline was administered in the saline/detorsion group. After 4 h of testicular detorsion in both of these groups, the rats were killed and bilateral orchiectomy was performed to determine the tissue levels of NO. The level of NO in the torsion group (113.77 ± 33.18 nmol/g protein) was significantly higher than that of the sham operation group (64.53 ± 29.64 nmol/g protein). In the saline/detorsion group, the NO level (31.26 ± 12.58 nmol/g protein) was significantly lower than in the torsion and sham operation groups. CAPE administration in the CAPE/detorsion group seemed to raise the NO level (72.63 ± 23.87 nmol/g protein) above the level of the sham operation group. Contralateral testes were not affected by the torsion/detorsion processes performed on the ipsilateral testes. These results show that NO levels increase with torsion and decrease with detorsion. CAPE administration seems to increase tissue NO levels and this may be important for protecting the testes from torsion/detorsion injuries. Received: 30 December 1999 / Accepted: 8 September 2000     

The role of nitric oxide in testicular ischemia-reperfusion injury

PURPOSE: This study was designed to determine the role of nitric oxide (NO) in the ischemia-reperfusion (I/R) injury process in testes. METHODS: Fifty prepubertal male rats were divided into 5 groups each containing 10 rats. After 4-hour torsion and 4-hour detorsion, bilateral orchiectomies were performed for measurement of tissue malondialdehyde (MDA) level and histopathologic examination. The results were compared statistically. The groups were labeled as group 1, basal values of biochemical parameters in testes; group 2 (control group), torsion plus detorsion; group 3, torsion plus N-monomethyl-L-arginine (L-NMMA) plus detorsion; group 4, torsion plus L-arginine plus detorsion; group 5, sham operation. RESULTS: The highest MDA values were determined in the L-arginin group in ipsilateral testes. Group 3 and group 4 were statistically different from control group. Histological examination showed that specimens from group 4 had a significantly (P < .05) greater histological injury than group 3, and contralateral testes showed normal testicular architecture in all groups. CONCLUSIONS: These results suggest that NO plays an important role in damaging the testis with I/R. Although inhibition of NO synthesis with L-NMMA significantly improves I/R injury in testes, enhancing NO production by providing excess of L-arginine increases such damage. In the early periods of detorsion, there is no damage to contralateral testes after unilateral testicular torsion.