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     

N-硝基-L-精氨酸甲酯对大鼠隐睾生殖细胞凋亡的保护作用

目的探讨一氧化氮合酶(NOS)抑制剂N-硝基-L-精氨酸甲酯(L-NAME)对大鼠隐睾生殖细胞凋亡的保护作用.方法用22 d SD雄性大鼠复制单侧隐睾模型.实验分假手术组、隐睾组、隐睾+L-NAME组[术后腹腔注射L-NAME,10 mg/(kg·d)],每组大鼠各10只.术后7 d,用生物素-dUTP/酶标亲和素测定法检测睾丸生殖细胞凋亡,用硝酸还原酶法测定睾丸组织中NO含量,用化学比色法测定睾丸组织中NOS活性.结果术后第7 d,与假手术组睾丸相比,隐睾组睾丸发生凋亡的生殖细胞数显著增加,隐睾+L-NAME组睾丸发生凋亡的生殖细胞数比隐睾组显著减少(P＜0.01),隐睾+L-NAME组睾丸组织中NO含量及NOS活性与隐睾组相比显著降低(P＜0.01).结论隐睾组织中NO和NOS升高是隐睾生殖细胞凋亡增加的病理机制之一,L-NAME通过抑制NOS活性、减少NO的产生来降低睾丸组织生殖细胞的凋亡发挥其保护作用.     

汉防己甲素对肾病综合征大鼠肾小球细胞外基质的作用

目的探讨中药汉防己甲素(Tetrandrine)对单侧肾切除加两次注射阿霉素肾病综合征大鼠肾小球细胞外基质(ECM)的作用.方法将实验动物分为(1)正常对照组、(2)汉防己甲素治疗组、(3)氨氯地平治疗对照组和(4)模型组,于第12周留取尿标本,肾组织病理学检查和图像分析肾小球细胞外基质变化,计算ECM/肾小球面积(GA).结果汉防己甲素治疗组和氨氯地平组肾小球ECM均明显减少(ECM/GA为0.24±0.02、0.29±0.01比(4)组0.39±0.02)(P＜0.05)、球囊粘连减轻.结论汉防己甲素能减少肾病综合征大鼠肾小球ECM沉积,延缓肾小球硬化.     

Fas配体阳性睾丸细胞和环孢素A对移植胰岛细胞存活起协同保护作用

目的　探讨Fas配体 (FasL)阳性睾丸细胞与胰岛细胞共移植后联用环孢素A(CsA)对移植胰岛细胞存活的协同保护作用。　方法　将同种大鼠胰岛细胞与睾丸Sertoli细胞同侧或异侧共移植于 4 1只糖尿病SD大鼠受体肾包膜下。实验大鼠分 7组 ,术后酌用CsA ,观察各组大鼠移植物存活情况。　结果　单纯胰岛细胞移植 (对照组 )后胰岛细胞的平均存活期为 (4 6± 1 1)d ,加用CsA存活期明显延长至 (2 1 8± 4 7)d(P <0 0 1)。与 1× 10 7个睾丸细胞同侧共移植的胰岛细胞平均存活期超过 (5 7 5± 4 0 )d ,但如移植前先封闭睾丸细胞表达的FasL后 ,移植的胰岛细胞平均存活期缩短为(5 8± 2 6 )d。胰岛细胞与 1× 10 5个睾丸细胞分别共移植于两侧肾包膜下 ,术后联用CsA ,胰岛细胞的平均存活期超过 (5 5 0± 6 5 )d ,与 1× 10 7个睾丸细胞同侧共移植的存活期相近 ,但比对照组或CsA组则显著延长 (P <0 0 1)。当胰岛细胞与 1× 10 6个睾丸细胞分别共移植且不用CsA时 ,胰岛细胞存活期平均仅为 (11 5± 3 1)d ,但仍较对照组延长 (P <0 0 5 )。　结论　表达FasL的睾丸细胞与CsA联用后可通过不同机制抑制胰岛细胞移植排斥反应而起到全身的协保护作用。     

隐睾及睾丸固定术后对大鼠生精能力的影响

目的 观察隐睾及睾丸固定术后对睾丸生精能力的影响.方法 通过手术方法对80只SD大鼠制作单侧隐睾模型,随机分为10组,其中4组(每组10只)于隐睾术后7、14 d切取患侧睾丸组织,6组于隐睾术后7、14d行睾丸固定术,分别于术后2、4、6周取材.将所取得的睾丸组织称重后行流式细胞仪检测其细胞凋亡率和各生精细胞百分比以及组织中B淋巴细胞/白血病-2( bcl-2)和bax基因表达量.结果 隐睾睾丸重量明显下降,隐睾组1C细胞(7d组:10.61 ±1.10,14d组:11.79 ±0.91)较对照组降低(16.48±1.60,P＜0.05)、4C细胞也明显降低,而2C细胞(7d组:40.41±2.93,14 d组:51.41±6.45)较对照组增加(30.17±3.24,P＜0.05).隐睾各组生精细胞凋亡率(7d组:14.9±1.26,14 d组:6.90±0.96)高于正常对照组(2.50±0.44,P＜0.01),而睾丸复位固定术后各组生精细胞凋亡率均下降(P＜0.05).隐睾7、14 d睾丸中bc1-2蛋白表达量(7d组:4.68±0.47;14 d组:5.66 ±0.71)较对照组(7.47±1.01)降低而bax蛋白表达量(7d组:8.27±1.08;14 d组:6.26±0.21)较对照组(5.82 ±0.47,P＜0.05)升高,睾丸固定术后各组bcl-2蛋白表达量升高而bax蛋白表达量降低(P＜0.01).结论 隐睾可以使睾丸生精细胞凋亡增加,睾丸复位固定术后,睾丸生精功能可部分或全部恢复,其恢复程度和隐睾时间长短有关;bcl-2和bax表达在生精细胞凋亡的调控中起重要作用.     

单侧隐睾对患儿血清抗苗勒管激素及抑制素B水平的影响研究

目的:探讨单侧隐睾对患儿血清抗苗勒管激素(AMH)及血清抑制素B(INHB)水平的影响。方法:选取单侧隐睾患儿65例,健康对照组45例,在6月龄和12月龄时分别测量患儿阴茎长度、阴茎周径及隐睾侧睾丸体积,检测血清AMH及INHB水平。结果:单侧隐睾组12月龄时血清AMH[(103.26±17.57)ng/ml]及INHB[(70.21±5.69)pg/ml]较健康对照组[AMH:(108.06±12.40)ng/ml;INHB:(77.43±5.66)pg/ml]明显下降,差异均有统计学意义(P均0.05);单侧隐睾组和健康对照组在6月龄和12月龄时的阴茎长度、周径和隐睾侧睾丸体积无统计学差异(P均0.05),6月龄时血清AMH和INHB水平亦无统计学差异(P均0.05)。结论:单侧隐睾影响患儿睾丸功能,应及时行睾丸下降固定术以减轻隐睾对患儿睾丸功能的影响。     

吸烟对大鼠生精细胞发育影响的研究

目的:探讨吸烟对大鼠生精细胞发育的影响。方法:自制吸烟机将大鼠制成被动吸烟模型,大鼠随机分成被动吸烟组(A、B组各10只)及相应对照组(C、D组各10只),A、B组被动吸烟8周,随后处死A组及相应对照组C组大鼠;B组停止被动吸烟后与其相应对照组D组继续观察48 d后处死。流式细胞术(FCM)检测各组大鼠生精细胞周期,放免法测定血睾酮(T)、黄体生成素(LH)水平,HE染色观察睾丸组织结构变化,透射电镜观察睾丸超微结构改变。结果:与C组比较,A组大鼠精子、精子细胞[(18.76±3.58)%]和初级精母细胞[(5.71±1.18)%]明显减少(P均<0.01),而精原细胞[(55.98±5.35)%]增加(P<0.01),增殖指数降低(P<0.01)。A组大鼠生精小管壁变薄,层次减少,生精小管内精原细胞减少,精母细胞固缩。间质细胞内质网扩张脱颗粒,高尔基复合体减少,支持细胞脂滴和溶酶体增多。A组大鼠T、LH水平低于C组(P均<0.01)。B组大鼠停止被动吸烟后,精子、精子细胞、初级精母细胞比例和增殖指数上升,T、LH水平升高,但仍低于D组。结论:吸烟导致大鼠睾丸生精上皮损伤及间质细胞和支持细胞受损,同时伴有T和LH水平的下降,延缓生精细胞增殖,停止吸烟后生精功能有逐渐恢复的趋势。     

环磷酰胺对雄性大鼠生精功能的影响

目的 观察环磷酰胺对大鼠生精功能的影响.方法 8周龄成年雄性sD大鼠,分6组,每组16只.前5组为实验组,给药方法分别为每日10、20、40、80、100 mg/kg,另1组为对照组.胃管给药2周和4周后,处死大鼠,取附睾精子行CASA检查;取睾丸组织苏木素.伊红(HE)染色分析睾丸曲细精管结构变化,TUNEL法检测睾丸曲细精管细胞凋亡情况.留取血清标本采用电化学发光法检测性激索水平.结果 环磷酰胺每日40 mg/kg喂养4周,大鼠存活率93.8%,精子数量明显减少(29.36±8.64)X 106个/ml,精子活力降低(22.25±2.03)%,睾丸生精上皮细胞明显损伤变性(58.1±1.2)%,血清睾酮水平下降(0.149±0.020)μg/L.这些指标的变化与环磷酰胺给药剂量及时间旱负相关(P<0.05).结论 通过环磷酰胺诱导可以成功建立大鼠少精/无精症动物模型,环磷酰胺主要通过坏死和凋亡两种途径导致睾丸曲细精管结构变化,导致生精细胞减少并最终引起少精/无精症.     

实验性隐睾大鼠的抗精子自身免疫研究

目的　探讨大鼠隐睾模型中抗精子自身免疫的发生情况及其对双侧睾丸的影响。方法　将 2 2日龄SD雄性大鼠 2 4只随机分为隐睾组和假手术组各 12只 ,在日龄 110天时采血并处死。用ELISA法检测血清抗精子抗体 (AsAb) ,免疫组化 (SABC法 )检测睾丸组织的IgG复合物 ,并对睾丸生精功能进行评价。结果　隐睾组和假手术组的血清AsAb阳性率分别为 41.7%和 0 ,差异有显著性 (P <0 .0 5 ) ;隐睾组大鼠的隐睾及对侧睾丸的生精功能评分均显著低于假手术组的手术侧及对侧睾丸 (隐睾侧P <0 .0 0 1,对侧P <0 .0 5 ) ,隐睾组大鼠的睾丸组织IgG复合物的沉积程度与生精功能呈负相关 (隐睾侧r =- 0 .860 ,P <0 .0 0 1,对侧r =- 0 .693 ,0 .0 1

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一氧化氮合酶基因表达对实验性大鼠隐睾生殖细胞凋亡的影响

目的　研究诱生型一氧化氮合酶 (iNOS)及其mRNA表达与实验性大鼠隐睾生殖细胞发育、凋亡的关系。方法　 (1)采用SD雄性健康大鼠 16只 ,日龄 2 2天时复制单侧隐睾模型。 (2 )采用生物素 dUTP/酶标亲和素测定法检测睾丸生殖细胞凋亡。 (3)采用免疫组织化学方法检测大鼠睾丸生殖细胞中iNOS基因表达。 (4 )采用原位杂交法检测大鼠生殖细胞中iNOSmRNA的表达。结果　 (1)术后第 7天 ,与自身对侧正常睾丸相比 ,隐睾侧睾丸发生凋亡的生殖细胞数显著增加 (P <0 .0 1)。 (2 )单侧隐睾模型建立术后第 7天 ,在双侧睾丸的间质细胞、支持细胞和初级精母细胞中均可见iNOS蛋白及iNOSmRNA的弱阳性表达 ,在隐睾侧睾丸曲细精管中脱落的生殖细胞中可见iNOS蛋白及iNOSmRNA的强阳性表达。术后第 7天 ,与自身对侧正常睾丸相比 ,隐睾侧睾丸生殖细胞中iNOSmRNA表达显著增加 (P <0 .0 1)。结论　 (1)实验性大鼠隐睾可以导致睾丸生殖细胞凋亡增加。 (2 )iNOS蛋白及其mRNA的表达增加是隐睾生殖细胞凋亡增加的分子机制之一     

Immunohistochemical study of glutathione S-transferase in normal and experimental cryptorchid testes rats]

Using the antibody for glutathione S-transferase (GST) purified from human kidney, normal testes and experimental cryptorchid testes from newborn to 20-week-old rats were immunohistochemically stained by the peroxidase antiperoxidase (PAP) method. The cryptorchidism was surgically created at 1 week of age. The localization of GST was particularly examined by light microscopy, and the amount of Leydig cells was measured by a stereological method. 1. Leydig cells in the normal and cryptorchid testes showed strong GST activity at all ages. The amount of these cells in normal testes increased from 4 to 8 weeks of age and then slightly decreased, whereas in cryptorchid testes it was significantly larger than in the normal testes at 20 weeks of age, indicating hyperplasia of Leydig cells. 2. In the normal and cryptorchid testes, degenerating primary spermatocytes with GST activity appeared in the seminiferous tubules at 2 to 4 weeks of age. In the cryptorchid testis, degenerating germ cells with GST activity were also found in the regressing seminiferous tubules after 4 weeks of age. It is possible that GST acts as a detoxification system in the degenerating germ cells. 3. The PAP staining of GST in the rat testes is considered to be useful method for evaluating metabolic function of the spermatogenic cells and the distribution and amount of Leydig cells. 4. Experimental cryptorchidism showed that germ cells become sensitive after 4 weeks of age.     

Experimental cryptorchidism in the adult mouse: I. Qualitative and quantitative light microscopic morphology

Morphologic changes in the testes of adult mice after experimentally induced cryptorchidism were studied by light microscopy and stereology. Increasing duration of cryptorchidism resulted in a gradual decrease in the volume of seminiferous tubules per testis, and this was associated with germ cell degeneration. The volumes of Sertoli cell lipid droplets increased, and dilations of the intercellular space between the Sertoli cell junctions was observed in the cryptorchid testis. The luminal volume of the seminiferous tubule was reduced by 50% after 28 days of cryptorchidism. However, the volumes of intertubular tissue and Leydig cells in control and cryptorchid testes were not significantly different. Leydig cell number per testis increased, and the average volume of a Leydig cell decreased gradually with the progression of the cryptorchid state. The volume of the connective tissue cells in the intertubular area increased, but no significant volume change was observed in the volume of intertubular macrophages. After 28 days, the cryptorchid testis contained a significantly increased volume of blood vessels and a reduced volume of lymphatic space per testis. These observations clearly demonstrate that, although the mouse is a species closely related to the rat, the morphologic changes that occur in the Leydig cell population after induction of experimental cryptorchidism in this species is different.     

Leydig cell hyperplasia in cryptorchid patients: Quantitative evaluation of Leydig cells in undescended and contralateral scrotal testes

Summary Leydig cell number was evaluated quantitatively in testicular biopsies from post-pubertal cryptorchid patients and normal controls. For this quantitative evaluation we used the following method. This is based on the determination of the total number of Leydig cells, Leydig cell clusters and seminiferous tubules in the entire histologic sections of each biopsy and the determination of the following indices; mean Leydig cells per tubule, mean Leydig cell clusters per tubule and mean Leydig cells per cluster. In addition, the numbers of Sertoli cells were counted, and Leydig-Sertoli cell ratio was also determined. These indices were correlated with each other. All indices were significantly elevated not only in undescended but in contralateral scrotal testes of the cryptorchid patients in comparison to those in normal controls. Between undescended and descended scrotal testes of the same individual patients, those indices were significantly higher in the descended scrotal testes than in the undescended ones. Thus, Leydig cell hyperplasia was noted in the testes of post-pubertal cryptorchid patients, and was more prominent in the contralateral scrotal testes than in the undescended ones.     

Effects of experimental cryptorchidism and subsequent orchidopexy on seminiferous tubule functions in the lamb

The reversibility of damage caused by cryptorchidism to the seminiferous tubules of the lamb was investigated at various ages. Lambs were made bilaterally cryptorchid either at birth or at 2 months of age. Then orchidopexy was performed at either 2 or 4 months of age. In permanently cryptorchid lambs, spermatogenesis stopped completely, and Sertoli cell function, as measured by FSH receptors, androgen receptors and ABP, was much reduced (-96%, -86% and -81%, respectively). Orchidopexy allowed the cryptorchid seminiferous epithelium to grow again, but the more differentiated the germ cells, the less they were capable of restoration. Even in 0- to 2- and 0- to 4-month-old temporarily cryptorchid lambs that had recovered normal Sertoli cell function, 16 to 49% of the tubules still were empty. It was concluded that cryptorchidism irreversibly damages the seminiferous tubules at a level other than the hormone receptors.     

Morphometric studies on the testes of rats treated neonatally with oestrogen and subsequently with gonadotrophins and testosterone

The experiments involved male rats, which were given a single subcutaneous dose of 1 mg stilboestrol on the first day of life. Beginning on day 28, subgroups of the rats received either gonadotrophins or testosterone for 39 days. The weight of the testes, serum luteinizing hormone and testosterone levels were determined while sections of the testes were subjected to morphological analysis and morphometric measurements, based on computerized techniques. The results demonstrated that a single dose of oestrogen caused a reduction in the cross-sectional area of the seminiferous tubules and a reduction in the thickness of the seminiferous epithelium, accompanied by inhibition of spermatogenesis. The number of and area occupied by Leydig cells, as well as the size of their cell nuclei, were also diminished, and the levels of serum testosterone decreased by 73%. All the experimental animals manifested significantly increased serum luteinizing hormone levels. Stimulation with gonadotrophins markedly increased the number of Leydig cells, their size and the size of their cell nuclei. This was associated with significantly increased levels of serum testosterone. Under these conditions, the cross-sectional area of the seminiferous tubules and the thickness of seminiferous epithelium remained less than those in the untreated controls. Following stimulation with testosterone the pattern of the seminiferous tubules resembled that noted after stimulation with gonadotrophins; the number of Leydig cells was markedly reduced but the size of both the cells themselves and of their nuclei approached normal values.     

Effect of seminiferous tubule size on hCG-induced regeneration of peritubular Leydig cells in hypophysectomized, EDS-treated rats

Following their selective destruction 3 weeks previously by administration of ethane dimethanesulphonate (EDS) the regenerative capacity of Leydig cells was assessed in relation to seminiferous tubule morphology in hypophysectomized adult rats administered 7 daily injections of 100 iu hCG. Total Leydig cell volume per testis in hCG-treated rats (30.2 ±3.2 μl, mean ± SEM) was significantly ( p <0.01) greater than in the testes of rats at 3 and 4 weeks after EDS-treatment (7.6 ± 0.7 and 22.7 ± 1.4 μl, respectively). Regeneration of Leydig cells in hCG-treated rats significantly ( p <0.05) favoured peritubular locations (18.6 ± 2.8 μl/testis) compared to central or perivascular sites of origin (11.6 ± 1.2 μl/testis). Partial restoration of spermatogenesis occurred in hCG-treated rats (tubule diameters usually >250μm) and a significant inverse correlation was found between peritubular Leydig cell percentage, or total volume per testis, and the volumetric proportion of seminiferous tubules ( r =-0.94, p <0.001) or the seminiferous epithelium ( r =-0.73 to -0.79, p <0.05–0.01). No significant ( p >0.4–0.9) correlation existed between centrally-regenerated Leydig cells and these parameters. The results show that in response to hCG stimulation, Leydig cells are more likely to develop around smaller seminiferous tubules, suggesting that hCG alone cannot mimic the expected pattern of Leydig cell regeneration (central and peritubular origins) which occurs during normal sexual maturation or at 3–4 weeks after EDS treatment. It is concluded that other factors, possibly FSH, are required for typical Leydig cell development which in turn may be influenced by local cellular growth factors originating from either the seminiferous tubules or the adjacent intertubular tissue.     

Evolution of somatic and germ cell populations after busulfan treatment in utero or neonatal cryptorchidism in the rat

Summary.  In order to elucidate the respective effects of depletion of germ cells and of increase in testicular temperature, rats of the same Wistar strain were rendered experimentally bicryptorchid or sterilized by a busulfan injection in utero and compared to control animals. In both models, germ cells were depleted but numeric evolution and functions of somatic cells differed. The aim of that work was to compare the numeric evolutions of testicular somatic and germ cells to their respective functions in each model before puberty and in adult rats of the same strain. Serum concentrations of FSH, LH and testosterone were compared at 20, 40 and 110 days of age. Histological analyses of Sertoli and germ cells in the seminiferous tubules and of Leydig cells in the intertubular tissue were performed before puberty and at adulthood. Testosterone serum concentrations were depleted in both models starting at 40 days of age and more in busulfan-treated rats. Both FSH and LH levels were increased from 20 days onwards in experimental rats. Additional cryptorchidism in busulfan-treated rats depressed the serum testosterone concentration. At 17 days of age, the cryptorchidism do not modify somatic or germ cell populations while busulfan treatment has induced a decrease of both these populations. Conversely, the cross sectional area of the somatic testicular cells was not affected whatever the treatment. In adult testes of busulfan-treated and cryptorchid rats, the total numbers of Sertoli and Leydig cells and of germ cells per testis were decreased. The cellular size of the perivascular Leydig cells was not modified by any of the treatments whereas the size of the Sertoli cells was reduced.
In conclusion, in both models the absence of germ cells induces a decrease in Sertoli cell function, while the increase in testicular temperature provokes degeneracies of Sertoli and germ cells in the seminiferous tubules of the rat.     

Bilateral prepubertal testicular biopsies predict significance of cryptorchidism-associated mixed testicular atrophy, and allow assessment of fertility

INTRODUCTION: Mixed atrophy of the testis (MAT), a frequent finding in biopsies of formerly cryptorchid and/or infertile patients, is defined as the synchronous occurrence of both seminiferous tubules containing germ cells and Sertoli cell only-tubules in variable proportions. In tubules containing germ cells, different types of abnormalities in spermatogenesis may be seen. The presence of adult spermatids in the biopsy, even in small numbers, correlates with successful spermatozoa retrieval for "in vitro" fertilization techniques. Currently, it is unknown whether precursor lesions of MAT can be identified in cryptorchid patients during childhood. MATERIAL AND METHODS: Eighteen formerly cryptorchid adults who had undergone testicular biopsies in childhood had a repeat testicular biopsy to evaluate infertility. In prepubertal biopsies, abnormalities of the testicular parenchyma were classified into types I (slight alterations), II (marked germinal hypoplasia), and III (severe germinal hypoplasia). In postpubertal biopsies, the percentage of tubules containing germ cells and Sertoli cell only-tubules were estimated, as well as the presence of complete spermatogenesis. Abnormalities in spermatogenesis were classified into lesions of the adluminal or basal compartments of seminiferous tubules. RESULTS: Comparison between prepubertal and postpubertal biopsies revealed that most specimens developing from type III lesions presented with incomplete spermatogenesis (P<0.0001) and more severe lesions of the germinal epithelium (P=0.049). DISCUSSION: Type III lesions correlated with MAT characteristics that confer a worse prognosis for in vitro fertilization. Thus, MAT characteristics may be predicted in prepubertal cryptorchid patients, allowing a fertility prognosis. The pathogenesis of these lesions, and their possible inclusion into the spectrum of the testicular dysgenesis syndrome, are discussed.     

Experimental cryptorchidism in the adult mouse. III. Qualitative and quantitative electron microscopic morphology of Leydig cells.

The morphology of Leydig cells of control and 28-day-old cryptorchid mice was studied by electron microscopy and stereologic techniques. Leydig cell profiles of control mice were larger in section when compared to cryptorchid mice, but no differences were observed in the distribution of organelles in Leydig cells in the two groups. Quantitatively, the absolute volumes of smooth endoplasmic reticulum (SER), rough endoplasmic reticulum (RER), mitochondria, lysosomes, multivesicular bodies, peroxisomes, cytoplasmic matrix, nucleus, lipid droplets, membrane whorls, ribosomal aggregates, and annulate lamellae per Leydig cell were reduced significantly after 28 days of cryptorchidism. However, the absolute volumes of these organelles per testis were not significantly different between control and cryptorchid mice, due to the increase in Leydig cell number per testis in the cryptorchid testis, compared to the controls, except that the absolute volume of Golgi per Leydig cell was not significantly different between control and cryptorchid rats, but the absolute volume of Leydig cell Golgi was significantly lower in control rats. Based on these results, we conclude that, morphologically, a 28-day cryptorchid mouse Leydig cell clearly approximates a "half unit" of a control Leydig cell.     

The effect of selective destruction and regeneration of rat Leydig cells on the intratesticular distribution of testosterone and morphology of the seminiferous epithelium

This study was designed to explore the relationship between the intratesticular distribution of testosterone and spermatogenesis by completely destroying the Leydig cells of mature male rats with injection of a single i.p. dose of ethane dimethanesulphonate. After such treatment, testosterone levels in serum, testicular interstitial fluid, seminiferous tubules, and whole testis declined significantly 6 to 24 hours after injection and fell below assay detection limits between 3 and 7 days. At 3 and 7 days, serum LH and FSH levels rose significantly and remained elevated up to 4 and 6 weeks, respectively, in comparison with vehicle-treated controls. Leydig cells disappeared from the interstitium by day 3, but between 2 and 4 weeks postinjection a new generation of fetal-like Leydig cells repopulated the testicular interstitium and, during weeks 6 to 10, were transformed into, or replaced by, Leydig cells with an adult type of morphology. Histologic examination of the seminiferous tubules showed progressive disruption of spermatogenesis between 3 and 14 days post-ethane dimethanesulphonate. The first histologic sign of spermatogenic damage was noted at day 3, with the occurrence of stage-specific degenerating pachytene primary spermatocytes at stages VII to VIII of the spermatogenic cycle. On day 7, these cells and degenerating round, or step 19, spermatids often were observed during stages VII to XI, although qualitatively normal spermatogenesis also was seen in these and all other stages of the cycle. Maximum impairment of spermatogenesis occurred 2 weeks post-ethane dimethane sulphonate, at which time the tubules commonly lacked one or more germ cell generations or, alternatively, showed accumulation of lipid inclusions, extracellular spaces, and variable numbers of degenerating germ cells. Following repopulation of the testis by Leydig cells during weeks 3 and 4, spermatogenesis recovered. By 10 weeks after treatment, qualitatively normal spermatogenesis was seen in the great majority of seminiferous tubules, although a few tubules still remained in which the germ cell complement was severely reduced, and contained only Sertoli cells and spermatogonia.(ABSTRACT TRUNCATED AT 400 WORDS)