睾丸支持细胞和间质细胞在生精细胞凋亡中的作用

睾丸精子发生过程中存在生精细胞凋亡，支持细胞和间质细胞作为非生殖细胞对生精细胞凋亡具有重要作用。本文对这方面的研究作一综述。     

青春期糖尿病鼠性腺重量与性行为观察

Ｗｉｓｔａｒ大鼠４０只，４０日龄，分为对照组，胰岛素及时治疗糖尿病组，胰岛素延迟治疗糖尿病组和糖尿病组。观察６０天。结果表明，糖尿病显著降低了睾丸，附睾、精囊腺和前列腺的重量，降低了附睾精子计数和性行为能力。     

枸杞、黄芪对大鼠睾丸支持细胞功能的影响

目的:探讨中药枸杞、黄芪对大鼠睾丸支持细胞(Sertoli细胞)功能的作用及机制。方法:对18~22 d的SD大鼠睾丸Sertoli细胞进行分离培养,用MTT法检测枸杞(50、100、200、400μg/m l枸杞多糖)、黄芪(12.5、25、50、100 g/L黄芪提取液)对Sertoli细胞增殖的影响,用一步法RT-PCR方法检测枸杞、黄芪对正常培养状态和过氧化物(H2O2)损伤状态下Sertoli细胞抑制素(INH)βB亚基转录的影响。结果:高浓度枸杞(400μg/m l)、黄芪(100 g/L)对Sertoli细胞的增殖有促进作用(P<0.05),高浓度杞芪合剂(400μg/m l枸杞+100 g/L黄芪)对Sertoli细胞增殖有明显促进作用(P<0.01);在正常培养状态下,枸杞、黄芪及杞芪合剂对Sertoli细胞INHβB亚基的转录具有明显促进作用(P<0.01);在过氧化物(H2O2)损伤状态下,Sertoli细胞INHβB亚基的转录明显降低(P<0.01),黄芪对Sertoli细胞INHβB亚基的转录水平具有上调作用(P<0.05),枸杞、杞芪合剂对其转录水平具有明显上调作用(P<0.01)。结论:枸杞、黄芪及杞芪合剂对体外培养的Sertoli细胞INHβB亚基的转录具有促进和保护作用。     

皮质酮诱导青春期大鼠睾丸间质细胞凋亡的研究

本研究目的旨在观察皮质酮能否诱导青春期大鼠睾丸间质细胞凋亡,用皮质酮分别经体内、外途径处理大鼠睾丸间质细胞。凋亡细胞经碘化丙碇（ＰＩ）标记后用流式细胞仪检测。体外研究结果表明,经１００ｎＭ皮质酮处理２４小时后的睾丸间质细胞,其凋亡量（３６．５％）显著高于对照组（１２．７％。Ｐ〈０．０１）。在体研究得到类似结果,经皮质酮（２．５ｍｇ／１００ｇ体重）处理２４小时后的大鼠,其纯化的睾丸间质细胞调亡量（２     

睾丸支持细胞和间质细胞在生精细胞凋亡中的作用

睾丸精子发生过程中存在生精细胞凋亡，支持细胞和间质细胞作为非生殖细胞对生精细胞凋亡具有重要作用，本文对这方面的研究作一综述。     

局部高温对青春期前大鼠睾丸支持细胞波形蛋白的影响及其与生精细胞凋亡的关系

目的:探讨局部高温对青春期前大鼠睾丸支持细胞波形蛋白表达和分布的影响及其与生精细胞凋亡的关系。方法:选取青春期前SD大鼠40只,随机分为对照组8只和实验组32只,实验组按热处理后2、4、12、24h均分成4个亚组;通过对睾丸局部高温(43℃水浴15min)处理,对照组以22℃水浴15min处理,采用组织化学和免疫组化方法,分析高温对青春期前大鼠生精小管细胞形态结构、支持细胞波形蛋白表达与分布的影响,采用TUNEL法检测各组生精细胞凋亡情况。结果:与对照组比较,高温处理后2h及4h即可见生精细胞与支持细胞发生分离,且自基膜脱落至管腔,数目逐渐增多;免疫组化发现,对照组波形蛋白沿基膜形成环样并随支持细胞胞质向管腔伸展分布,2h组波形蛋白围绕支持细胞核周分布,伸至管腔的蛋白表达减少或消失,其表达量与对照组比较无差别,12h及24h组与对照组比较差异有显著性(P<0.01);凋亡检测表明,12h及24h组生精细胞凋亡明显增加,而2h及4h组生精细胞凋亡与对照组比较反而减少。结论:高温可导致支持细胞波形蛋白的表达增多及分布变化,其改变与生精细胞凋亡有密切关系,高温可能通过直接作用于支持细胞而破坏生精过程。     

青春期糖尿病鼠性腺重量与性行为观察

Ｗｉｓｔａｒ大鼠４０只，雄性，４０日龄，分为对照（Ｃ）组、胰岛素及时治疗糖尿病（ＤＣＩＲ）组、胰岛素延迟治疗糖尿病（ＤＤＩＲ）组和糖尿病（Ｄ）组。观察６０天。结果表明，糖尿病显著降低了睾丸、附睾、精囊腺和前列腺的重量，降低了附睾精子计数和性行为能力。胰岛素替代治疗明显改善了上述指标，及时治疗的效果优于延迟治疗     

青春期己烯雌酚暴露对大鼠睾丸发育及功能的影响

目的 探讨青春期己烯雌酚(diethylstilbestrol,DES)暴露对SD(Sprague-Dawley)大鼠睾丸发育及功能的影响.方法 35日龄雄性SD大鼠90只,随机分为DES 0.01、0.1、1.0、10.0 μg·kg-1·d-14个实验组和1个对照组(编码为Bda、BDb、BDc、BDd和BC组,每组18只).于青春期,即出生后第36天(postnatal day 36,PND 36)至PND 49,实验组每日皮下注射相应剂量的DES,共14 d,对照组仅注射溶媒.于青春期晚期(PND 50)、性成熟后(PND 64)和成年期(PND 130)分3批(每批6只)处死各组大鼠取材,测定睾丸重量,观察比较睾丸组织形态学变化,分析PND 130大鼠附睾尾精子质量.结果 PND 50时,BC、Bda、BDb、BDc和BDd组单侧睾丸重量分别为(1.26±0.13)、(1.23±0.20)、(0.99±0.15)、(0.85±0.23)和(0.60±0.04)g,其中BDb、BDc和BDd组均较BC组减轻(P＜0.05);与BC组比较,BDb组仅有少数生精小管生精上皮中的细胞数目稍减少,BDc和BDd组生精小管发育较差、生精上皮中细胞数目减少、精子发生阻滞、间质细胞发育幼稚,其程度随DES暴露剂量增加而加重.PND 64时,BC、Bda、BDb、BDc和BDd组单侧睾丸重量分别为(1.54±0.14)、(1.55±0.17)、(1.52±0.11)、(1.37±0.14)和(0.88±0.15)g,其中BDc和BDd组均较BC组减轻(P＜0.05);BDc和BDd组睾丸组织形态学改变与PND 50时类似,但较PND 50时有所改善.PND 130时,各实验组与对照组比较,单侧睾丸重量差异无统计学意义(P＞0.05),睾丸组织形态学改变未见明显差异;BC、Bda、BDb、BDc和BDd组大鼠附睾尾精子密度分别为(71.00±14.85)、(69.00±23.98)、(67.00±13.52)、(31.67±12.94)和(18.83±6.68)×106/ml,其中BDc和BDd组精子密度均较BC组明显降低(P＜0.01);与BC组比较,BDd组精子活动率下降(P＜0.01),BDb、BDc和BDd组A级精子比例降低(P＜0.05),BDd组B级精子比例降低(P＜0.01).结论 青春期小剂量DES(0.01μg·kg-1·d-1×14 d)暴露对SD大鼠睾丸发育及功能无明显影响,大剂量DES(1.0～10.0 μg·kg-1·d-1×14 d)暴露对大鼠睾丸发育及功能具有明显的近期(PND 50和PND 64)和较远期(PND 130)毒性作用,该毒性作用随DES暴露剂量增加而加重,随鼠龄增长而逐渐减退,其机制可能与间质细胞和支持细胞的发育及功能受损密切相关.     

大鼠睾丸支持细胞溶酶体的周期性变化

作者在透射电镜下观察了大鼠精子发生过程中支持细胞（Ｓｅｒｔｏｌｉ细胞）中溶酶体的结构及分布的改变。结果Ｓｅｒｔｏｌｉ细胞中溶酶体数目多，在细胞中所处的位置有周期性变化，细胞中全部胞质和在基底部胞质中溶酶体的截面积占胞质截面积的比例在生精第ＶＩＩ阶段最大，近腔部溶酶体截面积占胞质截面积在第ＩＩ、ＩＸ阶段最小；Ｓｅｒｔｏｌｉ细胞总胞质和在基底部单位胞质截面积的溶酶体数在第ＶＩＩ阶段最大，近腔部单位胞质截面积溶酶体数在顶体期后几阶段最大，第ＩＸ阶段最小。Ｓｅｒｔｏｌｉ细胞溶酶体的周期性变化是与生精细胞相互影响、相互作用，也是精子连续正常发生的前提条件之一。     

营养性肥胖对青春期雄性大鼠睾丸生精细胞凋亡的影响

目的:探讨营养性肥胖对青春期雄性大鼠睾丸生精细胞凋亡的影响。方法:健康雄性W istar大鼠40只,随机分为两组,每组20只,对照组给予普通饲料喂养,高脂组用高脂、高热量饲料喂养建立营养性肥胖大鼠模型,10周末处死大鼠摘取睾丸。全自动生化分析仪(ACA)检测外周血总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C);光镜观察睾丸组织病理学改变;TUNEL检测睾丸组织凋亡细胞;免疫组化法检测Bc l-2和Bax蛋白的分布和表达;RT-PCR法检测睾丸组织Bc l-2 mRNA和Bax mRNA的表达。结果:高脂组TC、TG、HDL-C和LDL-C(5.17±0.17、1.18±0.09、1.76±0.11、5.08±0.18)较对照组(1.38±0.12、0.39±0.05、0.97±0.07、0.75±0.06)显著升高(P<0.05);高脂组生精细胞凋亡指数(37.17±2.74)较对照组(5.16±0.81)显著升高(P<0.01),凋亡细胞以精原细胞和精母细胞为主;高脂组Bax蛋白和Bax mRNA(153.26±8.74、1.08±0.12)表达较对照组(101.81±6.14、0.37±0.04)明显升高(P<0.01);高脂组Bc l-2蛋白和Bc l-2 mRNA(139.26±7.21、0.46±0.05)表达较对照组(159.37±8.96、1.05±0.11)明显降低(P<0.01)。结论:营养性肥胖诱导大鼠睾丸生精细胞凋亡增多,其机制可能与Bc l-2表达降低和Bax表达升高相关。     

Early signs of Sertoli and Leydig cell dysfunction in the abdominal testes of immature unilaterally cryptorchid rats

Testicular descent was prevented unilaterally by cutting the gubernaculum testis of newborn rats. When 20 days old unilaterally cryptorchid rats were injected intraperitoneally with 2 μg bFSH per gram body weight and killed 6 h later when testicular testosterone (T) and oestradiol (E₂) concentrations were determined. The increase in E₂ was subnormal in abdominal testes. In 18-day-old unilaterally cryptorchid rats the efferent ducts were ligated bilaterally, and the rats were killed 48 h later. The weight increase, due to accumulation of seminiferous tubule fluid, was significantly greater in the abdominal testes. In contrast, the ABP content of the abdominal epididymis was subnormal in 20-day-old unilaterally cryptorchid rats. Unilateral orchidectomy was performed in 16-day-old unilaterally cryptorchid rats and at 20 days of age intratesticular T and E₂, and plasma FSH and LH concentrations were determined and compared to that in 20-day-old control unilaterally cryptorchid rats. Removal of an abdominal testis resulted in increased plasma FSH and intratesticular E₂, whereas plasma levels of LH and intratesticular levels of T were unaffected. Removal of a scrotal testis resulted in increased plasma FSH and LH coupled with increased intratesticular T and E₂. Rats with a single abdominal testis had higher plasma FSH and LH and intratesticular T, but similar intratesticular E₂, than rats with a single scrotal testis. It is concluded that Sertoli and Leydig cell function are influenced by cryptorchidism at a stage when the temperature difference, and the morphological differences between the testes are very discrete.     

Sertoli cell — Leydig cell interaction in the regulation of testicular function

Considerable evidence exists to indicate that the Leydig cells influence the seminiferous tubule by maintaining a high concentration of testosterone in the peritubular compartment of the testes. Recent studies using various types of agents to disrupt spermatogenesis, have shown that significant changes occur in the structure and function of the Leydig cells. In these situations, Leydig cells enlarge, show hyperresponsiveness to hCG stimulation in vitro and contain a reduced number of receptors for LH/hCG. Evidence is presented to support the hypothesis that the changes in Leydig cell structure and function are the result of local factors. The data provide support for the concept that the functioning of Leydig cells is modulated by the seminiferous tubules.     

Temperature and germ cell regulation of Leydig cell proliferation stimulated by Sertoli cell-secreted mitogenic factor: a possible role in cryptorchidism

Summary. Local control of Leydig cell morphology and function by seminiferous tubules was suggested in previous in vivo studies, especially those that used experimental cryptorchid rat testis as a model. These studies reported changes in morphology, increases in cell number and mitotic index and decreases in testosterone formation and luteinizing hormone/human chorionic gonadotropin receptor levels of Leydig cells. However, little is known about how these changes are mediated. We recently observed that a novel Sertoli cell-secreted mitogenic factor stimulated proliferation, decreased testosterone formation and luteinizing hormone/human chorionic gonadotropin receptor levels, and dramatically altered the morphology of Leydig cells in culture. In the present studies, we demonstrate that an increase in coculture temperature from 33 to 37 °C increased [³H]-thymidine incorporation (5.6- vs. 19.2-fold) and labelling index (4.3% vs. 15.8%), and accelerated proliferation (2.1- vs. 3.9-fold) of cultured immature Leydig cells. In addition, testosterone formation and luteinizing hormone/human chorionic gonadotropin receptor levels of Leydig cells cocultured with Sertoli cells were further decreased following a 4°C increase in coculture temperature. This elevation in culture temperature increased both the secretion of this factor by Sertoli cells and responsiveness of Leydig cells to this factor. In addition, the presence of germ cells, especially pachytene spermatocytes, inhibited the secretion of the mitogenic factor by Sertoli cells. These temperature- and germ cell-associated effects mimicked the morphological and functional changes of Leydig cells reported following experimental cryptorchidism. These observations suggest a possible role of this Sertoli cell-secreted mitogenic factor in explaining Leydig cell changes following experimental cryptorchidism.     

Effect of neonatal treatment of rats with potent or weak (environmental) oestrogens,or with a GnRH antagonist,on Leydig cell development and function through puberty into adulthood

This study addressed whether reduced Sertoli cell number or manipulation of the neonatal hormone environment has an influence on final Leydig cell number per testis in the rat, by applying neonatal treatments known to affect these parameters, namely administration of a GnRH antagonist (GnRHa) or diethylstilboestrol (DES, in doses of 10, 1 or 0.1 microg per injection). The effect of treatment with either of two 'environmental oestrogens', bisphenol-A (Bis-A) or octylphenol (OP), was also evaluated. Leydig (3beta-hydroxysteroid dehydrogenase immunopositive) cell development and function (plasma testosterone levels) were studied through puberty into adulthood. Treatment with GnRHa impaired testis growth, Leydig cell (nuclear) volume per testis and testosterone levels during puberty, when compared with controls, but final Leydig cell volume/number in adulthood was comparable with controls. As adult testis weight was reduced by 45% in GnRHa-treated rats, the percentage Leydig cell volume per testis was approximately double (p < 0.01) that in controls, and also at day 35. Testosterone levels in adulthood in GnRHa-treated rats were lower (p < 0.01) than in controls but were within the lower end of the normal range. Treatment with DES caused largely dose-dependent suppression of testis growth, Leydig cell (nuclear) volume per testis and testosterone levels up to day 35. Although by adulthood, Leydig cell volume/number per testis was comparable with controls in DES-treated rats, testosterone levels remained grossly subnormal. Neonatal treatment with either Bis-A or OP had little consistent effect on any of the parameters studied except that both treatments significantly elevated testosterone levels on day 18, as did treatment with DES-0.1 microg. The present findings are interpreted in the context of what is known about the hormonal regulation of Leydig cell development. These lead to the conclusion that final Leydig cell number per testis is not determined by the number of Sertoli cells per testis and appears not to be influenced in any major way by gonadotrophins, androgens or oestrogens in the first 2 weeks of postnatal life. This implies that adult Leydig cell number may be determined prior to birth.     

Non-tumoural parenchyma in Leydig cell tumours: pathogenetic considerations

Little is known about the pathogenesis of Leydig cell tumours (LCTs) of the testis. The observation of several associated dysgenetic features in the non-tumoural parenchyma and in the contralateral testes of men with testicular germ cell neoplasms has served as the basis to propose that there may be a common mechanism for different male reproductive disorders. However, the possible relationship between LCTs and other testicular lesions has not been explored. Here we describe the presence of primary lesions in the non-tumoural parenchyma of testes with LCT, from which we try to establish possible pathogenetic associations. We studied the non-tumoural parenchyma adjacent to 16 LCT specimens. Parameters as Leydig cell hyperplasia (LCHY), qualitative evaluation of the germinal epithelium and spermatogenesis, the presence of Sertoli cell-only tubules (SCOT), and the Sertoli cell nuclear morphology were consistently assessed in all cases. SCOT associated with Sertoli cell dysgenetic morphology was the most frequent finding, present in 50% of the cases. Another interesting finding was the presence of LCHY in four cases (25%). Abnormal spermatogenesis was found in 81.25% of the cases, and it consisted of lesions of the adluminal or basal compartments of seminiferous tubules. The occurrence of either dysgenetic Sertoli cells or LCHY adjacent to LCTs could represent primary anomalies, resulting from a common insult also involved in tumourigenesis. The abnormalities in spermatogenesis observed here are likely to represent consequences of either tumour compression or abnormal hormonal production. The significance of these associations merits further investigation regarding a common pathogenesis.     

The influence of age on Leydig cell function in patients with varicocele

In a large group of patients with varicocele (n = 108, mean age: 30.9 years) Leydig cell function was investigated by determining the plasma levels of gonadotrophins under basal conditions and after GnRH stimulation, and by measuring the plasma levels of 17-OH-progesterone (17-OH-P), testosterone (T), dihydrotestosterone (DHT) and oestradiol (E2). There was a significant positive correlation between age and the peak plasma LH values after GnRH stimulation (n = 48, r = 41, P less than 0.01). Conversely, an inverse correlation was observed between age and the basal plasma levels of 17-OH-P (n = 56, r = 0.47, P less than 0.01) and T (n = 108, r = 0.27, P less than 0.01). In normals controls of the same age range (n = 46, mean age: 30 years) such correlations were absent. In patients with varicocele, the 17-OH-P/T ratio was increased significantly in peripheral plasma under basal conditions (P less than 0.01) and after hCG stimulation (P less than 0.05), and a similar increase was found in spermatic venous blood. This suggests that in varicocele patients there is some enzymatic impairment involving the last steps of T biosynthesis. In order to verify the influence of ologozoospermia on plasma steroid levels we divided the patients into 2 groups according to sperm count (more than or less than 10 X 10(6)/ml). Three analyses of variance were then carried out between these 2 groups of patients: 1) analysis of peripheral plasma T levels; 2) analysis of peripheral plasma levels of 17-OH-P and 3) spermatic vein levels of these 2 steroids. However, none of these analyses revealed any significant difference between the 2 groups of patients. When we re-grouped the patients according to age (15-30 and 30-45 years) the same analyses of variance revealed significant differences. These results therefore suggest that the duration of idiopathic varicocele per se influences Leydig cell activity.     

糖尿病人胰岛素分泌功能差异对骨代谢的影响

为了解糖尿病人胰岛素水平的高低对骨代谢影响和程度,检测其馒头餐前后胰岛素和血糖水平,用跟骨超声波传导速度（ＳＯＳ）、振幅衰减（ＢＵＡ）和骨硬度指数（ＳＴＩ）。结果显示糖尿病各组ＳＯＳ、ＢＵＡ及ＳＴＩ均低于对照组,其中以胰岛素分泌低下组最明显,分泌延迟组和分泌过高组比较无显差异。组间比较,胰岛素分泌低下组胰岛素水平最低,而相应时限血糖值最高。胰岛分泌过高组胰岛素水平最高,但相应血糖值高于对照组,并