丙烯酰胺的雄性生殖毒性

丙烯酰胺在工业和科研实验中广泛应用，是一种较为常见的化工原料。近年来证实，丙烯酰胺还存在于高温加热的淀粉类食品中。丙烯酰胺具有多种毒性效应，近年研究发现丙烯酰胺具有生殖毒性，表现为对雄性生殖行为、雄性生殖内分泌功能和精子生成的影响等几个方面，其可能的机制包括丙烯酰胺作用于睾丸间质细胞，与马达蛋白、染色体和DNA形成烷化物以及通过氧化损伤来影响雄性生殖。     

丙烯酰胺的雄性生殖毒性

丙烯酰胺在工业和科研实验中广泛应用,是一种较为常见的化工原料。近年来证实,丙烯酰胺还存在于高温加热的淀粉类食品中。丙烯酰胺具有多种毒性效应,近年研究发现丙烯酰胺具有生殖毒性,表现为对雄性生殖行为、雄性生殖内分泌功能和精子生成的影响等几个方面,其可能的机制包括丙烯酰胺作用于睾丸间质细胞,与马达蛋白、染色体和DNA形成烷化物以及通过氧化损伤来影响雄性生殖。     

机动车尾气雄性生殖毒性的研究进展

本文主要从机动车尾气对动物、动物后代的生殖毒性及人群流行病学研究以及人类对机动车尾气生殖毒性的保护性研究等方面,就机动车尾气对雄性生殖毒性的研究最新进展进行了综述,旨在对机动车尾气的生殖毒性有更全面的认识。     

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。     

镉诱导的雄性生殖毒性及其拮抗药物

随着当今社会城市化和工业化进程的加快,镉已经成为一种普遍存在的有毒重金属和环境污染物.自然和人为活动可导致土壤镉污染,使得大米、蔬菜以及包括烟草在内的植物镉蓄积严重.人类由于接触镉污染环境、长期吸烟或摄入被镉污染的食物导致镉在体内蓄积.大量研究证实,镉进入机体后可导致肝、肾损伤[1],对生殖系统也有影响.镉在人体内的半...     

石墨烯对生殖毒性的研究进展

石墨烯是一种由碳原子以sp2杂化轨道组成六角型呈蜂巢晶格状的二维碳纳米材料.石墨烯具有很多优异的性质,比如光学、力学以及电学特性,在各个方面都有广泛的用途.石墨烯也是职业暴露中最常见的纳米材料之一.生殖毒性的研究是毒理学研究和评价一种物质全身毒性的重要组成部分.因此,本文就石墨烯对生殖毒性的研究现状进行综述,以期为石墨...     

睾丸细胞生物学研究进展

睾丸是男性生殖腺,由生精小管和间质构成。生精小管主要由生精细胞和支持细胞组成,是精子发生场所;间质中主要是间质细胞,间质细胞合成与分泌雄激素。本文介绍睾丸3种细胞的发育分化,以及成年期睾丸细胞的结构和生物学研究进展。     

生精合剂对雄性大鼠性激素水平及生殖功能的影响

目的 观察生精合剂对去除一侧睾丸雄性大鼠性激素水平及生殖功能的影响.方法 给去除一侧睾丸雄性大鼠灌胃生精合剂10d、30d后,分别测定血浆睾酮,促卵泡激素(FSH),促黄体生成素(LH)及精子计数和活力.结果 实验组能明显提高去除一侧睾丸雄性大鼠的血浆性激素水平,改善精子数量及质量.讨论生精合剂是通过直接补充外源性睾酮和调节下丘脑.垂体.性腺轴功能来提高去除一侧睾丸雄性大鼠的雄激素水平,同时通过多重因素的作用来提高精子数量及活力.     

直链烷基苯磺酸钠对雄性小鼠生精功能亚慢性毒性作用研究

目的 探讨直链烷基苯磺酸钠(LAS)对雄性小鼠生精功能的亚慢性毒性作用及毒性遗留作用. 方法 NIH种雄性小鼠给予LAS(630 mg/kg,315 mg/kg)灌胃,每日1次,连续经口染毒2个月,同时设对照组.在第4、8周及停止染毒后4周进行精子形态学观察,光镜观察睾丸组织形态学变化,透射电镜观察睾丸超微结构变化. 结果 实验组与对照组相比,染毒4周后精子畸形率上升,畸形主要表现在颈部,精子中部胞浆小滴增多.染毒8周精子畸形率升高更显著.组织学检查实验组小鼠染毒4周时精细小管内各级精母细胞和精子细胞数减少,生精细胞排列紊乱,随实验时间延长及染毒浓度的增加此异常改变更显著;超微结构观察显示睾丸生精上皮内支持细胞、间质细胞、精原细胞线粒体广泛异常改变,呈时间及浓度依赖性.上述异常改变在停止染毒后4周无明显恢复. 结论 LAS对雄性小鼠生精功能亚慢性毒性作用及毒性遗留作用表现为:使生精上皮内支持细胞、间质细胞及精原细胞出现广泛线粒体空泡样变,精子胞浆小滴出现率升高.     

药物性睾丸损害

药物副作用的研究一直倍受临床重视 ,尤其是药物对肝肾的影响更为医患所关注 ,但药物对睾丸的损害 ,却常因缺乏症状而长期被忽略。近年欧美报告因药物、食品添加剂等有毒物造成的睾丸损害逐年增多[1] ,国内就此研究的报告尚少 ,现复习近年国内外有关文献 ,就药物睾丸损害的研究     

Concentrations of polychlorinated biphenyls in blood and the risk for testicular cancer

An increasing incidence of testicular cancer has been reported from several western countries during the last decades. According to current hypothesis testicular cancer is initiated during the foetal period and exposure to endocrine disruptors such as some persistent organic pollutants has been of concern. We have previously reported the results for concentrations of polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl-dichloroethylene (pp'-DDE), hexachlorobenzene (HCB) and chlordanes in 58 cases with testicular cancer, 61 age-matched controls and 44 case mothers and 45 control mothers. In that report, significant increase of odds ratio (OR) was found for sum of PCBs, HCB, trans- and cis-nonachlordane in case mothers. These data have now been further analysed for 37 congeners of PCBs. No significant differences were found among cases and controls. However, case mothers had significantly increased concentrations of a number of PCB congeners. A priori decided grouping of PCBs yielded for oestrogenic PCBs OR = 2.4, 95% confidence interval (CI) = 0.95-6.0, enzyme-inducing PCBsOR = 2.6, 95% CI = 1.03-6.5 and toxic equivalents (TEQ) yielded OR = 3.3, 95% CI = 1.3-8.4. These data further elucidate the role of foetal exposure to different PCB congeners in the aetiology of testicular cancer.     

Sites of Action of Cyproterone and Cyproterone Acetate in the Immature Male Rat

Plasma testosterone (Leydig cell function), LH and FSH (pituitary function), the epididymal content of androgen binding protein (ABP) (Sertoli cell function) and plasma corticosterone (adrenal cortical function) were determined after 10 daily injections of varying doses of cyproterone and cyproterone acetate, beginning at 21 days of age. Daily doses of 0.5 mg or greater of either antiandrogen resulted in a marked depression in the levels of plasma testosterone and intra-testicular testosterone (measured only in the cyproterone group) with a dose-dependent decrease in testis and epididymal weights; both effects occurring with only minor changes in the levels of circulating gonadotrophins. In addition, these compounds caused a marked decrease in Sertoli cell secretion as reflected in a significant fall in the epididymal content of ABP.
A more detailed examination of the apparently direct effects of cyproterone on Leydig cell function revealed: 1) no major effects of in vivo treatment for 6 days (5 mg/day) on [I¹²⁵]hLH binding to testis membrane particles or on the in vitro response of enriched Leydig cell suspensions to hCG, 2) a dose-dependent inhibition of the hCG responsiveness of normal Leydig cells in the presence of the drug in vitro . The inhibitory effects on steroidogenesis in vivo can well be explained by a direct inhibition of the 3β-steroid-dehydrogenase-isomerase exerted by both antiandrogens.     

Attractin蛋白在大鼠睾丸和附睾中的免疫组织化学定位

目的 :探讨Attractin蛋白在成熟大鼠睾丸和附睾组织中的分布。　方法 :健康成年雄性SD大鼠 2 0只 ,灌流取睾丸和附睾组织固定 ,石蜡包埋和冰冻切片。用免疫组化法和间接免疫荧光方法检测Attractin蛋白在成熟大鼠睾丸和附睾组织中的表达。　结果 :睾丸组织间质细胞、睾丸精曲小管管周肌样细胞和各级生精细胞 (精原细胞、初级精母细胞和精子细胞 )、支持细胞呈阳性反应 ,主要表达于胞膜及胞质。睾丸间质细胞表达略强于生精细胞。附睾头、体、尾均未见表达。　结论 :Attractin蛋白在成熟大鼠睾丸组织间质细胞和生精细胞中有较强的表达 ,其生理功能尚有待进一步探讨。     

Changes in the secretion of ABP into testicular interstitial fluid with age and in situations of impaired spermatogenesis

Androgen-binding protein (ABP) was measured in serum and testicular interstitial fluid (IF) from rats during sexual maturation or in adult rats in which impairment of spermatogenesis had been induced by (i) testosterone withdrawal following Leydig cell destruction, (ii) local heating (43 degrees C) of the testes for 30 min or (iii) induction of unilateral cryptorchidism (UCD). The changes observed were related to the IF levels of testosterone and, in most instances, to the serum levels of FSH. The levels of ABP in serum and IF decreased together with age, being highest at 30 days, falling steeply by 40 days and then slowly but progressively up to 100 days of age. A similar pattern was observed for serum FSH, except that the initial fall occurred beyond 40 days of age. Treatment with EDS or exposure to local heating caused comparable reductions in testicular weight (25-30% by 7 days after treatment, 50% by 21-28 days) and raised the serum levels of FSH. In both groups the levels of ABP in IF were increased by two- to three-fold while the levels of testosterone were either reduced markedly (EDS-treatment) or remained unchanged (local heating). In rats made UCD for 60 days, the weight of the abdominal testis was reduced by 75%, compared with the contralateral scrotal testis, while the IF levels of ABP and testosterone were significantly increased (55%) and decreased (90%), respectively. Short-term (3 days) deprivation of testosterone in adult rats, following immunoneutralization of LH, was without significant effect on IF levels of ABP. It is concluded that ABP secretion into IF is increased in situations of subnormal (or sub-adult) numbers of germ cells and this is usually associated with high levels of FSH. Measurement of ABP levels in IF should prove of value for the monitoring of Sertoli cell function in vivo and may be of diagnostic use for the detection of changes in germ cell numbers.     

环境雌激素致雄性生殖系统发育异常途径的研究进展

大量动物实验表明环境雌激素(EEs)具有生殖和(或)发育毒性,其致雄性生殖系统发育畸形的机制复杂,尤其作用途径目前仍很不明了。本文从EEs干扰睾丸发育、影响睾丸激素产生、代谢并进而致雄性生殖系统发育畸形的可能途径介绍近年来国内外取得的进展。     

Effects of Roselle and Ginger on cisplatin-induced reproductive toxicity in rats

Aim:To evaluate the protective effects of Hibiscus sabdariffa(Roselle)and Zingiber officinale(Ginger)againstcisplatin-induced reproductive toxicity in rats and to study the mechanisms underlying these effects.Methods:Ethanol extracts of H.sabdariffa or Z.o fficinale[1g/(kg.day)]were given p.o.to male albino rats for 26 days,which began 21 days before a single cisplatin i.p.injection(10 mg/kg body weight).Results:Extracts of H.sabdariffaand Z.officinale reduced the extent of cisplatin-induced sperm abnormality and enhanced sperm motility.Bothextracts restored the control level of malondialdehyde(MDA)(lipid peroxidation marker)in the cisplatin-treated testis.The cisplatin injection induced decline in the levels of superoxide dismutase(SOD),reduced glutathione(GSH)andcatalase(CAT)were significantly reversed to control levels in groups where cisplatin was preceded by the administra-tion of either H.sabdariffa or Z.officinale.Conclusion:Both H.sabdariffa and Z.officinale treatment increasedthe activities of testicular antioxidant enzymes and restored sperm motility of cisplatin-treated rats.The protectiveeffects of tested plants are,therefore,suggested to be mediated by their potent antioxidant activities.(Asian J Androl2006 Sep;8:607-612)     

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.     

Effects of single polychlorinated biphenyls on the morphology of cultured rat tubuli seminiferi

The effects of single polychlorinated biphenyls (PCB) on isolated tubuli seminiferi of the rat were studied. Freshly isolated rat tubuli seminiferi were prepared according to their transillumination pattern, i.e. dark or pale. Tubuli seminiferi with the dark pattern included stages II to VIII and tubuli with the pale pattern represented stages IX to XIV and stage I of the seminiferous cycle. Afterwards, tubuli seminiferi were exposed to single polychlorinated biphenyls for 5 or 24 h in vitro. PCB 126, PCB 77, and PCB 118 were used in final parts per billion (p.p.b.) concentrations as determined by quantitative PCB analysis. Eventually, the specimens were plastic embedded, cut into semithin sections, stained, and morphology was evaluated by light microscopy. Single PCB congeners induced morphological alterations in cultivated rat tubuli seminiferi in a time- and stage-dependent manner. Effects comprised loosened intercellular contacts between germ cells and Sertoli cells as well as cellular fragmentation in the layer of round spermatids. Early spermiogenesis seems particularly susceptible to single PCB congeners in concentration of background magnitude. The target cell has still to be discovered.