生殖股神经在单侧隐睾鼠对侧睾丸损害中的作用机制

目的：探讨生殖股神经在单侧隐睾鼠模型对侧睾丸损害中的作用机制。方法：建立单侧隐睾鼠模型（21d龄），切断该侧生殖股神经，120d后观察对侧睾丸的生精细胞凋亡及细胞乳酸含量变化。结果：切断生殖股神经后对侧睾丸生精细胞凋亡减少，乳酸含量降低，乳酸含量与细胞凋亡呈正相关。结论：单侧隐睾症对侧睾丸损伤可能与其神经传导反射性血流减少引起生精细胞凋亡有关。     

单侧隐睾大鼠生殖股神经在对侧睾丸损害中的作用机制研究

目的 :探讨单侧隐睾大鼠模型生殖股神经在对侧睾丸损害中的作用机制。　方法 :建立单侧隐睾大鼠模型 (2 1d龄 ) ,切断该侧生殖股神经 ,12 0d后观察对侧睾丸的生精细胞凋亡变化及组织乳酸含量变化。　结果 :切断生殖股神经后 ,对侧睾丸生精细胞凋亡为 (5 .76± 0 .76 ) % ,与对照组 (17.2 8± 1.36 ) %相比明显减少 (P <0 .0 5 ) ;乳酸含量也由 (2 .19± 0 .2 4 )mmol/L下降为 (1.70± 0 .31)mmol/L(P <0 .0 5 ) ,且乳酸含量与细胞凋亡呈正相关(P <0 .0 5 )。　结论 :单侧隐睾症对侧睾丸损伤可能与其神经传导反射性血流减少引起生精细胞凋亡有关     

Undescended testis is accompanied by calcitonin gene related peptide accumulation within the sensory nucleus of the genitofemoral nerve in trans-scrotal rats

PURPOSE: Recent data suggest that calcitonin gene related peptide (CGRP) released from the sensory branch of the genitofemoral nerve may regulate testicular descent. We studied the number of CGRP immunoreactive cells in the sensory nucleus of the genitofemoral nerve (L1 to L2 dorsal root ganglia) in cryptorchid trans-scrotal rats. Four-week-old trans-scrotal rats with unilateral undescended testis underwent bilateral genitofemoral nerve dissection and retrograde nerve labeling with the fluorescent dye 4,6-diamidino-2-phenylindole (DAPI). Animals were sacrificed 48 hours later and the L1 to L2 dorsal root ganglia were removed. Serial sections were obtained and double fluorescent labeled with antibody to CGRP. Retrograde labeled and CGRP immunoreactive cells were counted using an epi-fluorescent microscope.In the 6 male trans-scrotal rats evaluated we noted a mean plus or minus standard deviation of 1,272 +/- 98 retrograde labeled dorsal root ganglion cells ipsilateral to a fully descended testicle, including 98 +/- 34 that were also CGRP immunoreactive. On the side of the undescended testis there was a mean of 1,600 +/- 304 DAPI positive cells and 160 +/- 51 CGRP immunoreactive, DAPI labeled cells. The difference was significant (p <0.02).This study shows that in trans-scrotal rats the sensory nucleus of the genitofemoral nerve contains more CGRP immunoreactive cells ipsilateral to an undescended testis than on the contralateral side, highlighting the significance of CGRP supply through the sensory branch of the genitofemoral nerve for testicular descent.     

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.     

大鼠一侧睾丸扭转对侧睾丸改变的实验研究

目的 :研究一侧睾丸扭转 (UTT)后对侧睾丸组织学及生精细胞凋亡的改变 ,以明确UTT后对侧睾丸是否存在损伤。　方法 :SD雄性大鼠 6 0只 ,随机分为实验组 (n =4 8)及对照组 (n =12 )。实验组采用Turner方法建立左侧睾丸扭转模型 ,于扭转后 6h处死 4只 ,其余 4 4只再分为扭转睾丸复位及切除组 ,分别于术后 1d、1周、4周处死7～ 8只 ,取睾丸组织进行组织学及生精细胞凋亡的检测。　结果 :UTT复位后对侧睾丸组织学发生明显改变 ,生精细胞凋亡指数明显高于对照组 (P <0 .0 5 )。扭转睾丸切除后对侧睾丸变化不明显。　结论 :UTT可引起对侧睾丸损伤 ,其机制可能与再灌注有关 ,扭转睾丸切除可防止或减轻对侧睾丸的损伤     

Reperfusion injury after detorsion of unilateral testicular torsion

Summary Reperfusion injury has been well documented in organs other than testis. An experimental study was conducted to investigate reperfusion injury in testes via the biochemical changes after unilateral testicular torsion and detorsion. As unilateral testicular torsion and varicocele have been shown to affect contralateral testicular blood flow, reperfusion injury was studied in both testes. Given that testicular blood flow does not return after 720° testicular torsion lasting more than 3 h, the present study was conducted after 1 and 2 h of 720° torsion. Adult male albino rats were divided into seven groups each containing ten rats. One group served to determine the basal values of biochemical parameters, two groups were subjected to 1 and 2 h of unilateral testicular torsion respectively, two groups were subjected to detorsion following 1 and 2 h of torison respectively, and two groups underwent sham operations as a control. Levels of lactic acid, hypoxanthine and lipid peroxidation products were determined in testicular tissues. Values of these three parameters obtained from the sham operation control groups did not differ significantly from basal values (P>0.05). All three parameters were increased significantly in both ipsilateral and contralateral testes after unilateral testicular torsion when compared with basal values (P<0.01 and P<0.05, respectively). Detorsion caused significant changes in lipid peroxidation products levels in ipsilateral but not in contralateral testes when compared with values obtained after torsion (P<0.01 and P>0.05, respectively). It is concluded that ipsilateral testicular torsion causes a decrease in perfusion not only in the ipsilateral but also in the contralateral testis. Additionally, detorsion following up to 2 h of 720° torsion causes reperfusion injury in ipsilateral but not in contralateral testis.     

Ipsilateral and contralateral testicular blood flows during unilateral testicular torsion by133Xe clearance technique

Testicular blood flows during unilateral testicular torsion were measured by Xenon-133 clearance technique. Xenon-133 was injected via the left carotid artery into the heart. Measurements were performed in control and left-sided testicular torsion groups, each consisting of ten rats. Left and right testicular blood flows, which were 29.157±2.272 ml/100 g/min and 29.773±2.934 ml/100 g/min in the controls, were 11.983±3.655 ml/100 g/min and 16.098±3.757 ml/100 g/min in the experimental group and differed significantly. The decrease in contralateral testicular blood flow may play an important role in the contralateral testicular damage encountered following unilateral testicular torsion.     

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.     

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.     

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.     

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.     

血管内皮细胞生长因子和内皮型一氧化氮合酶在大鼠单侧隐睾对侧睾丸损害中的表达

目的 探讨大鼠隐睾中内皮型一氧化氮合酶(eNOS)和血管内皮细胞生长因子(VEGF)的表达与单侧隐睾对侧睾丸损害的关系.方法 将45只雄性SD大鼠(22 日龄)随机分成单侧隐睾并生殖股神经离断组(A组)、单侧隐睾组(B组)和假手术组(C组),每组15只.动物模型建立后(65日龄),苏木素-伊红(HE)染色观察睾丸生精上皮形态,原位缺口末端标记法(TUNEL)检测对侧睾丸生精细胞的凋亡,免疫组织化学和Western blot方法检测对侧睾丸组织中eNOS和VEGF基因表达的变化.结果 B组相对于A组和C组对侧睾丸组织中生精细胞的凋亡率最高(t1=3.04,t2=3.94,t1,t2＞t28,P＜0.01),Western blot和免疫组织化学方法检测结果也显示B组eNOS和VEGF的表达含量较A组和C组都显著升高,差异有统计学意义(P＜0.01),而A组和C组的各指标差异均无统计学意义(P＞0.05).结论 eNOS和VEGF的高表达和生殖股神经在单侧隐睾对侧睾丸的损害中起重要作用,而切断生殖股神经可以阻断这一损害过程.

Abstract：

Objective To study the relationship between the expression of endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) with the damage of contralateral testis of unilateral cryptorchidism in the experimental rats. Methods Forty-five immature male Sprague-Dawley rats (aged 22 days) were randomly divided into the group A (unilateral cryptorchidism and the ipsilateral genitofemoral nerve division), group B (unilateral cryptorchidism), group C (sham operation), n = 15 in each group. When the rats were aged 65 days, all the rats were sacrificed and the testes were obtained. The morphological changes of the spermatogenic epithelium in the testes were observed, and the germ cell apoptosis was detected by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) technique. The expression of eNOS and VEGF was detected by using Western blotting and immunohistochemistry in the testicular tissues.Results The germ cell apoptosis was increased significantly ( t1 = 3. 04, t2 = 3. 94, t1 ,t2 ＞ t28 , P ＜0. 01) , and the levels of eNOS and VEGF in the contralateral testes were also increased obviously in group B as compared with groups A and C ( P ＜ 0. 01) , but the entire indexes in groups A and C had no significant difference. Conclusion eNOS, VEGF and genitofemoral nerve play a important role in the damage of the contralateral testes of unilateral cryptorchidism, and the damage can be prevented by genitofemoral nerve division.     

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.     

Histological and immunohistochemical studies on the damage of contralateral testis following the unilateral testicular torsion in Wistar rats

The effect of experimental unilateral torsion of the testis on the contralateral intrascrotal testis in Wistar rats was evaluated histologically and immunohistochemically. The results were summarized as follows. 1) Histological damage of the seminiferous tubules in the contralateral testis was present only in adult rats. 2) The histological change 3-5 weeks after the experimental torsion consisted of marked decrease of spermatocytes, loss of spermatids and spermatozoa and numerous Sertoli-cell only tubules. Hyperplasia of the interstitial cells was demonstrated without thickness of the basement membrane and infiltration of the inflammatory cells. The tubular diameter and the ratio of contralateral testicular weight to rat body weight were significantly decreased (p less than 0.05) in torsion group. 3) Using an indirect immunofluorescent method, the positive immunohistochemical staining on spermatid and spermatozoa of normal testicular tissue was demonstrated using only the serum of rat with histological damage on the contralateral testis. Therefore, the phenomenon may be ascribable to the presence of antisperm antibody. It is concluded that the mechanism of the damage in seminiferous tubules of the contralateral testis with experimental torsion in adult Wistar rats is related to the humoral immunity producing antisperm antibody.     

未成熟大鼠睾丸单侧扭转后对健侧血流和组织学的影响

目的:观察未成熟大鼠睾丸单侧扭转后对健侧睾丸血流供应和组织学的影响,并比较不同处理方法的疗效。方法:建立Wistar3周龄大鼠左侧睾丸扭转模型,分别建立对照组、扭转组、扭转复位组和扭转切除组,每组10只。彩色多普勒测量各组术前、术后8h(即扭转复位或切除术后2h)、12h、24h、72h右侧睾丸动脉收缩期最大血流速度,并于对照组和扭转组术后2h,扭转复位组和扭转切除组第1次术后12h各取2只大鼠右侧睾丸进行组织病理学观察。各组喂养至9周龄时分别取右侧睾丸进行组织学观察及检测各组大鼠右侧睾丸的生精小管直径(STD)、生精上皮细胞计数(CMSE)和睾丸活检评分(TBS)。结果:①未成熟睾丸左侧扭转后,右侧睾丸的血供呈持续性增加。②扭转组、扭转复位组和扭转切除组右侧睾丸均有不同程度的间质水肿和超微结构改变。③9周龄时扭转组、扭转切除组右侧睾丸重量均较对照组显著增加(P<0.01);各组大鼠STD、CMSE、TBS均无显著性差异(P>0.05)。结论:未成熟大鼠睾丸单侧扭转后可引起对侧睾丸的血供增加和组织学改变,轻微损伤后扭转复位和睾丸切除预后效果相似。     

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。     

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.     

Pubertal genitofemoral nerve division induces testicular ascent in adult rats

BACKGROUND/PURPOSE: Ascending testes, which normally are located at the bottom of the scrotum in early infancy and later ascend back out of the scrotum, have been reported by several investigators. However, little is known about the effect of the division of the genitofemoral nerve (GFN) on testicular ascent as boys grow. The purpose of this study is to investigate whether the division of the proximal genitofemoral nerve in prepubertal rats induces testicular ascent in adulthood. METHODS: Thirty-day-old Wistar King A Rats (n = 27) underwent a unilateral proximal GFN transection on either the right or left side. At 150 days of age, the rats were killed, and their testicular position was examined. The length of the processus vaginalis was measured, and the testes were removed and weighed. Sham-operated rats were used as controls (n = 10). Student's t and the chi2 test were used for the statistical analysis. RESULTS: At 150 days of age, 21 of the 27 operated rats (77.8%) showed unilateral testicular ascent on the operated side. All testes were located at the bottom of the scrotum in sham-operated control rats (20 testes). Both the length of the processus vaginalis and the testicular weight were decreased significantly more on the operated side than in the sham-operated rats. CONCLUSIONS: These findings suggest that the proximal division of the genitofemoral nerve in prepubertal rats may induce a relative ascent of the testis by preventing the growth of the processus vaginalis in adulthood. In patients with such ascending testes, an abnormal development or accidental trauma of the genitofemoral nerve may be involved in testicular ascent.     

Effect of testicular torsion on the contralateral testis

It has been previously shown that unilateral testicular torsion can cause disruptive anatomic changes in the contralateral testis in rats [1]. In this experimental study plasma and urine prostaglandin E2 levels were studied correlatively with testicular histopathology in acute testicular torsion cases. As a result of this study, necrobiotic morphologic alterations causing testis necrosis and significant increase in plasma prostaglandin E2 levels were observed. Contralateral testicular histology was analyzed in all dogs. None of them showed abnormal tubular architecture.     

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.