The number of spermatogonia in various congenital testicular disorders

Various congenital testicular disorders, including monorchism, retractile testis, cryptorchidism and male intersex, were investigated by counting the number of spermatogonia per seminiferous tubule. The results showed that all 7 cases of monorchism had normal numbers of spermatogonia per seminiferous tubule. However, in 29 cases of a retractile testis a normal testis was observed in 13 (44.8 per cent). Therefore testicular dysgenesis is suggested to exist in more than half of cases of the retractile testis. Of 150 cases of cryptorchidism 82 were bilateral and 68 were unilateral. There was no significant difference in the number of spermatogonia per seminiferous tubule between these 2 groups. The higher the testes were located the worse the ratio of spermatogonia per seminiferous tubule. Fewer or absent spermatogonia were observed in 2 patients less than 2 years old. Of 28 contralateral scrotal testes in patients with unilateral cryptorchidism 4 (14.3 per cent) had no spermatogonia per seminiferous tubule and 8 (28.0 per cent) had a decreased number of spermatogonia per seminiferous tubule. The male intersex patients had much damage even in the scrotal testes. From these results it is suggested that these congenital testicular disorders, except monorchism, have similar histological features. Moreover, these conditions are possibly related in etiology to the phenomenon of deficient androgen stimulation.     

Morphologic effects of orchiopexy or orchiectomy on the contralateral testis in experimental unilateral cryptorchidism

For evaluation of the effects of orchiopexy and orchiectomy on the contralateral descended testis, unilateral cryptorchidism was produced in 60 21-day-old mice by suturing of the left testis to the inner abdominal wall. A sham operation was performed on the left testis of 20 control mice (S). After creation of unilateral cryptorchidism, orchiopexy (P) or orchiectomy (O) was performed on the left testis at 2 (group I) and 10 (group II) weeks (ten mice each). All testes were removed for examination 2 weeks after orchiopexy or orchiectomy. In both groups the mean values of testicular weight, seminiferous tubular diameter, and tubular biopsy score of contralateral O testes were always statistically similar to the values of contralateral S testes (p greater than 0.01). The difference between TBS values of contralateral P and S testes was not significant in group I (p greater than 0.01), but it was significant in group II (p less than 0.01). The data from this murine experiment suggest that orchiectomy for unilateral cryptorchid testis is almost always helpful in improving contralateral morphology; however, orchiopexy can be helpful if it is not performed late in the period of maturation.     

The natural course of cryptorchidism in rats and the efficacy of orchidopexy or orchidectomy in its treatment before and after puberty.

Both clinical and experimental evidence suggest that fertility is impaired in unilateral cryptorchidism. To investigate the effect of the undescended testis on the contralateral descended gonad, a new experimental model based on natural cryptorchidism in rats was designed. Seventy male Buffalo rats with an undescended right testis noted at the age of 30 days were used. Fifty healthy animals served as a controls. The natural course of cryptorchidism was investigated at the ages of 30, 90, and 180 days. The effects of orchiopexy and orchiectomy performed in cryptorchid animals before and after puberty were evaluated at the age of 180 days. Both nonoperated and operated animals were mated at the age of 150 days in order to estimate their fertility. The animals were killed at 30, 90, and 180 days of life and the testes were removed. In each excised testis testicular weight and seminiferous tubular diameters were measured and the maturity of the germinal epithelium was determined using the Johnsen testicular biopsy score. The experiment demonstrated reduced testicular weight and seminiferous tubular diameters in undescended testis already at 30 days and arrest of spermatogenesis at the spermatocytes stage at 90 and 180 days. There was no significant difference between contralateral descended testes and controls at the age of 30 and 90 days, but at 180 days the degenerative changes were identical with those in the cryptorchid testes. Cryptorchid rats were completely infertile. Both orchiopexy and orchiectomy prevented the damage to the contralateral testis. A significant improvement in size and spermatogenesis was recorded in most cases of the surgically descended testes.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effects of human chorionic gonadotrophin on normal testicular tissue of rats: dose-dependence and reversibility

OBJECTIVE To investigate the effect of human chorionic gonadotrophin (hCG) on rat testicular tissue, and its reversibility and dose dependence. MATERIALS AND METHODS Male Wistar rats were assigned to groups (10 rats/group) receiving 10, 30 or 50 IU/kg hCG subcutaneously once daily for 15 days; 10 controls received subcutaneous isotonic saline. At 1 and 3 months later, five rats in each group were killed and their testes removed. The testes were examined histologically to measure seminiferous tubular diameter and germinal membrane thickness. RESULTS At 1 month after hCG administration, the mean germinal membrane thickness in the testicular tissues of the hCG-treated rats was significantly less than in control rats, and was also significantly different between all of the hCG-treated groups (P < 0.05). However, at 3 months after hCG administration, all histological variables were similar to those in control rats (P > 0.05), and the mean germinal membrane thickness at 3 months after hCG administration was larger than that at 1 month (P < 0.05). There were no significant differences in the mean seminiferous tubular diameter between hCG-treated rats and control rats. CONCLUSION hCG impairs seminiferous tubule histology in the 'normal' descended testes of rats. This effect was dose-dependent, and the changes were reversed at 3 months after treatment. Thus, although hCG therapy might affect the seminiferous tubules of contralateral descended testes in cryptorchid boys, these effects might be reversible.     

Human chorionic gonadotropin deteriorates the histology of rat testes

OBJECTIVES: It is not yet certain whether early hormonal treatment in cryptorchidism is safe for germ cells. We investigated the histologic effects of human chorionic gonadotropin (hCG) therapy on descended testes of rats. DESIGN AND SETTING: Thirty male Wistar albino rats were randomized into two groups. The rats of the hCG group (n=15) were administered 50 IU/kg/day hCG once daily via the subcutaneous route for 15 days. Fifteen rats received subcutaneous isotonic saline and acted as controls. At the first month, testicular tissue was obtained after scarification in both groups. The histological examination was performed to evaluate the seminiferous tubular diameter, germinal membrane thickness, and the percentage of the open seminiferous tubule lumen in each testis to compare the two groups. RESULTS: The percentage of the open seminiferous tubular lumen in testicular tissues of hCG-treated rats was higher than that of controls (p<0.05). The mean germinal membrane thickness in testicular tissues of the hCG group was statistically lower than that of the control group (p<0.05). There was no statistical difference between mean seminiferous tubular diameter in testicular tissues of hCG-treated rats and controls, as expected (p>0.05). Additionally, there were two interesting cases of Sertoli cell only appearance in the hCG group. CONCLUSIONS: We may assume that hCG impairs the seminiferous tubule histology in normal testes of rats. Thus, further experimental studies on dose dependency and the reversibility of these effects are warranted.     

Effects of spermatic vascular division for correction of the high undescended testis on testicular function

Orchiopexy with division of the spermatic artery and veins is a commonly used technique for correcting the high undescended testis, although the longterm results have not been clearly defined. The left spermatic artery and veins of 22 adult Wistar albino rats were divided while preserving the vessels associated with the vas and cremaster muscle (DT). A sham operation was performed on the left testicle of six additional rats (ST). At 3 weeks postoperatively, both testes from all rats were removed. All testes were viable and bled when incised, although bleeding was considerably reduced in testes with DT. Mean testicular weights after DT were 1,061 +/- 423 mg compared with 1,634 +/- 125 mg for ST rats (p less than 0.02) and 1,508 +/- 119 mg for contralateral testes. The mean tubular diameter after DT was 220 +/- 37 mu compared with 303.1 +/- 10.7 mu for ST testes (p less than 0.02). The testicular biopsy score based upon the morphology of the spermatic tubules was 4.46 +/- 3.32 for DT testes and 8.65 +/- 0.23 for ST testes (p less than 0.02) compared with 8.38 +/- 0.18 for contralateral testes and an absolute normal value of 10. No morphologic abnormalities were observed in the contralateral unoperated testes from any of the rats. The contralateral testes in 12 additional rats were removed before DT. The mean testosterone values in these rats with one testicle was 1.43 +/- 0.75 ng/mL. Three weeks after DT, testosterone values were 0.19 +/- 0.31 ng/mL (p less than 0.01). It is concluded that division of the main spermatic artery and vein in rats produces testicular atrophy with spermatogenic arrest and interstitial cell dysfunction. Although collateral blood flow to the testis may be demonstrated, tissue perfusion is inadequate for normal spermatogenesis and endocrine function.     

Ultrastructure of the seminiferous tubules in oligoasthenoteratozoospermic men associated with varicocele

Varicocele is associated with venous reflux that may cause increased heat and interstitial pressure within the testes, with variable pathological effects on spermatogenesis. This study aimed to study the ultrastructural testicular changes in the seminiferous tubules of 20 infertile severe oligoasthenoteratozoospermia (OAT) men associated with varicocele and five patients with obstructive azoospermia without varicocele as controls. They were subjected to testicular biopsy which was evaluated by transmission electron microscopy. Ultrastructurally, the seminiferous epithelium in the testicular biopsies of infertile severe OAT men associated with varicocele was variably affected in the form of thickening of the peritubular connective tissue, vacuolation of Sertoli cell and germ cell cytoplasm, presence of degenerated and apoptotic cells among the germinal epithelium, altered spermatids and abnormal spermatozoa. It is concluded that varicocele in severe OAT men is associated with ultrastructural changes in the seminiferous tubule.     

Assessment of germ cell apoptosis in cryptorchid rats

Aim: To investigate the relationship between germ cell degeneration and apoptosis in cryptorchid rats. Methods: Thirteen 21-day-old Wistar rats were made unilaterally cryptorchid by closing the left inguinal canal. At day 30 (Group 1, n=6) and day 60 (Group 2, n=7) after operation, the testes were removed for histopathological examination. The controls (n=8) were sham operated and were sacrificed at day 60. Germ cell apoptosis was assessed by means of the TUNEL method. Results: Spermatogenesis was arrested and the testicular and seminiferous tubular diameters were significantly reduced In the unilateral undescended testes (UUTs) compared with the contralateral descended testes (CDTs) and the control rats. However, atrophic changes, pathological calcification, necrosis of seminiferous tubule, and absence or sloughing of germ cells were not found in all the animals. The spermatocytes were the main type of germ cells undergoing apoptosis in all the groups. In the UUTs, there was a significant and time-depe     

Effects of hypothermia on testicular ischemia

The ischemic effects of prolonged testicular torsion have been well documented; however, prevention or arrest of the damaging effects of prolonged ischemia has been incompletely studied. Two groups of Sprague-Dawley rats were subjected to varying lengths of bilateral testicular ischemia. Group I underwent normothermic ischemia for two, four, and six hours. Likewise, Group II underwent similar time periods of ischemia, however, after thirty minutes of normothermic ischemia the scrotum of each animal was placed into an ice bath maintained at 4C. Two weeks postoperatively, bilateral orchiectomy was performed. Histology of the testes of the two groups was compared. Neither group revealed significant destruction of the germinal epithelium after two hours of ischemia. Group I revealed only 25% preservation of the germinal epithelium at four hours and only 8% preservation at six hours of ischemia. In contrast, Group II which received ice showed 90% preservation of germinal epithelium at four hours and 85% preservation at six hours of ischemia. We conclude that external ice application significantly preserves seminiferous tubules at four and six hours of ischemic injury in the rat testicle.     

Testicular torsion: Evaluation of contralateral testicular histology

Infertility may occur in patients with unilateral testicular torsion whose contralateral testis is intact. Depending on this observation, the physicians have begun to examine the contralateral testis. In the present prospective study we aimed to examine the histopathologic alterations occurring in the contralateral testicle with time. Sixty adult male albino rats were included in the programme, and following experimental torsion the histopathologic findings, especially those in the contralateral testis, were evaluated after 4–12 weeks. Long-term and high degree torsion of the testicle led to varying degrees of deterioration in the germinal epithelium and interstitial cells of the contralateral testicle. Histopathologic alterations were reversed in 12 weeks. Tubular diameter and testicular volume also decreased in accordance with the histopathologic alteration. In our opinion, orchiectomy following torsion of one testicle will limit potential histopathologic alterations in the contralateral testicle.     

What lessons can be learned from testicular histology in undescended testes?

Over the last 40-50 years studies involving thousands of testicular biopsies in boys with cryptorchidism have contributed to our knowledge of testicular histopathology and our understanding of the effects of cryptorchidism on the normal development of the germinal epithelium. Growth and maturation of germ cells and Leydig cells are crucial to allow boys to reach normal fertility potential. The following aberrations in testicular development are seen in cryptorchid testes: a decrease in total germ cell numbers, failure of fetal gonocytes (stem cells) to transform into adult dark (Ad) spermatogonia, failure for Ad spermatogonia to mature into primary spermatocytes, Leydig cell hypoplasia, and testicular fibrosis. All of these findings have been found to have a strong negative correlation with a boy’s age at the time of orchidopexy. Some of these findings have prognostic significance in regards to fertility potential especially when coupled with key clinical findings such as hormonal findings, age at orchidopexy, testicle size, laterality and location of cryptorchid testes. This review focuses on key lessons learned from testicular histology in cryptorchid testes.     

Does orchidopexy revert the histological alterations in epididymal and vas deferens caused by cryptorchidism?

Cryptorchidism is a pathological condition in which the testicles are retained in the abdominal cavity, resulting in atrophic seminiferous tubules. Some gross structural abnormalities and histological altercations have been described in the epididymis and vas deferens in humans with cryptorchidic testes. Orchidopexy surgery restores testicular spermatogenesis in experimental and clinical procedures, but it is still unclear whether histological changes in the epididymis and vas deferens caused by cryptorchidism may be reverted by orchidopexy. The aim of this study was to evaluated the histological changes in the epididymis and vas deferens following experimental uni- bilateral cryptorchidism in mature and immature mice, and to determine whether altercations could be reversed by orchidopexy. Young and adult C57 BL6 mice were randomized into three groups: control mice, bi/unilaterally cryptorchidic mice and bilaterally cryptorchidic mice with orchidopexy. After evaluation of testis, epididymis and vas deferens, there were no histological alterations in contralateral epididymis of mice unilaterally cryptorchidic. Ipsilateral epididymis of unilaterally cryptorchidic mice and epididymis from bilaterally cryptorchidic mice showed significant histological alterations. Orchuidopexy resorted normal spermatogenesis and the histological features of epididymis. It would appear that persistent male infertility clinically observed after orchidopexy could not be related to histological alteration in the testis and epididymis. Development and maintenance of the vas deferens seems to be controlled independently of the epididymis since it was not altered by cryptorchidism condition.     

A study of cryptorchidism. III: The histochemistry of complex carbohydrates in the testes of cryptorchid patients

The complex carbohydrates in the undescended and contralateral scrotal testes of patients with cryptorchidism, were examined by light microscopic histochemical methods, in comparison with those of normal testes. In the undescended testes, histochemical reactions for acidic and neutral complex carbohydrates were apparently weaker than in the normal testes, especially pronounced in the seminiferous tubular walls. In the germinal and supporting cells of the undescended testes, the amount of galactose residues in the complex carbohydrates decreased from the prepubertal to post-pubertal periods. Periodic acid-Schiff reaction also revealed a decrease in the glycogen content in the germinal and supporting cells of the undescended testes from pre-pubertal to post-pubertal periods.     

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。     

Ischemia,whether from ligation or torsion,causes ultrastructural changes on the contralateral testis

OBJECTIVE: Unilateral testicular torsion results with a decrease in contralateral testicular blood flow caused by a reflexive sympathetic response. The aim of this study was to investigate whether twisting of the spermatic cord, or testicular ischemia without twisting, activates this reflex mechanism and causes ultrastructural changes in the contralateral side. MATERIALS AND METHODS: Thirty adult male albino Wistar rats were randomly allocated into three groups of sham, torsion, and ligation. Right testes were twisted 720 degrees counterclockwise in the torsion group. Right spermatic cords were ligated permanently with a silk suture including the vas deferens in the ligation group. After 24 h of testicular ischemia, contralateral left testes were removed for electron microscopic evaluation. RESULTS: Contralateral testes showed similar ultrastructural changes in the torsion and ligation groups. The fibrous tunica propria enveloping the seminiferous tubule was thickened due to increased collagen fibers. The basal lamina was continuous but thickened and showed several foldings. The gap between basal lamina and the germ cells was increased because of collagen fibers. Leydig cells showed mitochondrial degeneration with the loss of its cristae. Leydig cells lost their contact with its neighborhood cells in some areas, and these gaps were filled with collagen fibers. Germ cells showed dilated cisternae of smooth endoplasmic reticulum, cytoplasmic electron-dense bodies and clear regions. CONCLUSIONS: Similar electron microscopic findings observed in the torsion and ligation groups indicate that testicular ischemia rather than twisting of the spermatic cord is responsible for the ultrastructural changes in the contralateral side.     

Relative Positions of the Spermatogenic Stages in the Mouse Testis: Morphological Evidences for their Non-Randomized Adjacencies

The topographical distribution pattern of the stages of the murine seminiferous epithelium cycle was investigated. PAS-hematoxylin stained testicular sections from adult mice representative of the apical, equatorial and caudal region of both testes, were used. The relative frequencies (RF) of the stages of the seminiferous epithelium cycle was estimated on the basis of more than 10,000 cross-sectioned seminiferous tubules identified according to the criteria of Leblond and Clermont (1952). It was found that in the testicular sections the stages of adjacent seminiferous tubules are not distributed randomly. The comparison of the RF of the stages (calculated over all the testicular sections) with the RF of the stages that are adjacent to a given seminiferous tubule stage suggests a clustered occurrence of numerically identical stages. These comparisons very often show statistically significant differences. The finding of such associations among adjacent segments of seminiferous tubules (stages) suggest the existence of an ordered distribution of the seminiferous tubules inside the testis possibly controlled by substances with local control capacity of spermatogenesis. On the basis of the findings here presented, it is suggested an interpretation of the phenomenon of modulations of the waves of the seminiferous epithelium.     

Quantitative testicular biopsy in spinal cord injured men: comparison to fertile controls.

Spermatogenic abnormalities have been reported in the majority of spinal cord injured men on routine testicular biopsy. However, given the interim advances in their urological and rehabilitative care, a quantitative assessment of the germinal epithelium after spinal cord injury and comparison of these parameters to normal controls are warranted. Incisional testicular biopsy was performed in 14 spinal cord injured men. Quantitative micrometric techniques were applied to assess spermatogenesis and the results were compared to a normative data base of testicular biopsies previously obtained from a group of 15 fertile volunteers. From a minimum of 10 randomly selected round seminiferous tubules per subject the mean number of Sertoli cells, mature spermatids, tubular diameter and tubular wall thickness were determined in both groups and statistically analyzed. In the spinal cord injury group the mean number of spermatids per tubule was significantly lower and the mean number of Sertoli cells per tubule was significantly higher than in fertile controls (p less than 0.05). Moreover, the mean Sertoli cell-to-spermatid ratio per seminiferous tubule was significantly higher in the spinal cord injury group and discriminated between spinal cord injured men and controls, with a sensitivity of 93% and specificity of 100% (p less than 0.0001). Half of the spinal cord injury group showed a mean tubular spermatid density of less than 10. Compared to the fertile population, spinal cord injured men show significant differences in quantitative parameters of the germinal epithelium that may contribute to the reproductive dysfunction.     

Intratesticular factors and testosterone secretion: The effect of treatment with ethane dimethanesulphonate (EDS) and the induction of seminiferous tubule damage

The role of seminiferous tubule dysfunction in regulating the levels of a factor (or factors) in testicular interstitial fluid (IF) which stimulates Leydig cell testosterone secretion in vitro, was assessed by injecting rats with the Leydig cell toxin, EDS. Within 72 h of treatment EDS destroyed the Leydig cells and concomitantly reduced IF testosterone to undetectable levels. This was associated with nearly a 2-fold increase (P less than 0.001) in levels of the IF-factor(s) as judged by the enhancement of hCG-stimulated testosterone production (= IF bioactivity). By 3 weeks, and thereafter up to 10 weeks post-EDS, Leydig cells regenerated within the testis, and testosterone levels returned to control values, but IF-bioactivity remained significantly increased. The latter was associated with seminiferous tubule dysfunction as indicated initially by testicular morphology, raised serum levels of FSH and reduced testicular weight. For animals with normal testosterone levels, there was a significant negative correlation (r = -0.57, N = 46; P less than 0.001) between testicular weight and IF bioactivity. A similar increase in IF bioactivity in the presence of normal testosterone levels was observed in rats in which patchy severe seminiferous tubule damage had been induced by short-term cryptorchidism. It is concluded that, in addition to testosterone, seminiferous tubule function may dictate the intratesticular levels of the testosterone-stimulating factor(s) in IF.     

新生小鼠睾丸组织和作为异种移植物的人类胎儿睾丸组织在免疫缺陷小鼠中的发育情况(英文)

目的:采用同种和异种睾丸组织移植的方法,研究新生小鼠睾丸组织及人类未成熟睾丸组织异种移植物在免疫缺陷小鼠体内发育不同时期生精细胞的组成和基因表达情况中生精细胞的发育情况。方法:以免疫缺陷小鼠为受体,新生小鼠睾丸组织和人类未成熟睾丸组织为供体,分别进行同种和异种移植。通过对移植物的组织形态学观察和分子生物学检测,对各个时期同种移植物中的生精细胞组成及其特异性基因的表达情况进行评估并与末受损小鼠的情况相比较;对人睾丸组织异种移植物的存活及其生精细胞在异体异位的发育情况进行探讨。结果:新生小鼠睾丸组织在成年雄性去势免疫缺陷小鼠体内的发育状况在移植开始的一个阶段与在体睾丸组织的发育情况基本相同,各级生精细胞的出现及其基因表达均与在体睾丸组织中相类似,而移植7-8星期后生精小管发生退化现象。人未成熟睾丸组织在受体中存活并且进一步生长;组织学观察还发现,生精细胞的发育速度与在体相比具有加速的倾向。结论:新生小鼠睾丸组织同种移植物的发育与在体情况基本相同,而人类未成熟睾丸组织异种移植物的发育与正常生理状态相比较呈现出加速的倾向。     

The Effect of Low-Dose HCG on the Testis of Prepuberal Dogs

Tubule size and the changes of various enzyme activities in response to low doses of HCG were investigated in prepuberal dogs. After administering a total dose of 1000 IU over a period of five weeks, there was no significant alteration of the surface area of the seminiferous tubules as compared to controls. Histochemical studies of a number of hydrolases and oxido reductases of the germinal epithelium and interstitium did not show any changes in activity as compared to those of untreated animals. The results indicate that the low doses of HCG suggested by the International Health Foundation for treatment of cryptorchidism do not lead to marked alterations in the testicular tissue.