嫁虫戚精巢的组织学研究

本文研究了嫁虫戚雄性生殖系统的组织学。嫁虫戚的精巢结构同贻贝、栉孔扇贝的相似,也是由外膜及其内的无数生殖小管构成。外膜较薄,由平滑肌和少量结缔组织组成,只在局部区域含有单层柱状上皮细胞。生殖小管间充填着结缔组织及来自外膜的薄层肌肉,结缔组织中含有血管。生殖小管由位于基膜上的生殖上皮及由生殖上皮增殖出的精原细胞、初级精母细胞、次级精母细胞、精细胞和精子组成。精原细胞较大,圆形或椭圆形,核较大,与细胞同形,染色质呈颗粒状靠近核膜分布,核仁1个,圆形,明显。初级精母细胞和次级精母细胞结构相似。精细胞圆形,核染色深。精子呈长棒状,悬浮于生殖小管腔内。     

脊尾白虾的性腺发育及组织结构观察

为系统研究脊尾白虾的性腺发育及组织学特征,采用常规的石蜡切片及H.E染色方法对脊尾白虾的性腺发育及其组织结构进行观察。结果表明,脊尾白虾的雌性生殖系统由卵巢、输卵管及排卵孔组成。卵子发生经历了卵原细胞、卵黄合成前期卵母细胞、内源性卵黄合成期卵母细胞、外源性卵黄合成期卵母细胞,最后发育为成熟的卵母细胞。卵巢发育可分为增殖期、小生长期、大生长期、成熟期及产后恢复期。脊尾白虾雄性生殖系统由精巢、输精管及排精孔组成。精巢由生精小管构成,不同生精小管内精子发育可不同步。精子发生经历了精原细胞、初级精母细胞、次级精母细胞、精细胞,最后发育为精子。输精管可分为前、中、后输精管及末端壶腹,精荚在输精管中形成。     

嫁(虫戚)精巢的组织学研究

本文研究了嫁Qi雄性生殖系统的组织学。嫁Qi的精巢结构同贻贝、栉孔扇贝的相似，也是由外膜及其内的无数生殖小管构成。外膜较薄，由平滑肌和少量结缔组织组成，只在局部区域含有单层柱状上皮细胞。生殖小管间充填着结缔组织及来自外膜的薄层肌肉，结缔组织中含有血管。生殖小管由位于基膜上的生殖上皮及由生殖上皮增殖出的精原细胞、初级精母细胞、次级精母细胞、精细胞和精子组成。精原细胞较大，圆形或椭圆形，核较大，与细胞同形，染色质呈颗粒状靠近核膜分布，核仁1个，圆形，明显。初级精母细胞和次级精母细胞结构相似。精细胞圆形，核染色深。精子呈长棒状，悬浮于生殖小管腔内。     

克氏原螯虾雄性生殖系统的超微结构

采用透射电镜研究了克氏原螯虾输精管的超微结构,采用石蜡切片法研究了克氏原螯虾的精巢、输精管和精荚的显微结构,并对精巢做了周年变化研究。结果表明,精巢由许多生精小囊和收集管组成,其结构呈葡萄串状,生殖细胞在生精小囊内发育成熟后由收集管输送到输精管;输精管有左右两条,相对于左侧输精管,右侧输精管比其约长一半,直径更大,卷曲程度更高,内容物含量更多,分泌细胞内的内质网含量更丰富;输精管根据形态不同分为前、中、后、生殖突4段,前中段具有分泌精荚壁物质的功能,后段具有储存、射出精荚的功能,末端生殖突为输精管出口;精荚呈长囊形或椭球形,由精子团、精荚基质和两层精荚壁组成,精子团偏向精荚一侧分布;克氏原螯虾雄虾精巢在一周年中的5—8月和10月处于精子细胞期的生精小囊比例很高,具有两个成熟时期。     

[4]东海三疣梭子蟹精子发生及精荚形成

为探究东海三疣梭子蟹(Portunus trituberculatus Miers,1876)雄性群体的性腺发育规律,通过定期采样,运用形态学、组织学方法对东海三疣梭子蟹精子发生及精荚形成过程进行了研究,并结合精小叶生殖节段法对处于不同发育阶段的精巢进行了定性分析.结果表明,三疣梭子蟹精巢属于叶型,由精小叶和精小管组成的叶状管交织而成.精子发生过程与其他高等短尾派蟹类相似,精子成熟后即进入精小管中.输精管可能起源于精小管.三疣梭子蟹精巢和输精管的发育存在一定的年际变化.4-5月份,精巢小叶内精原细胞占优势,输精管内精荚零星分布;6-7月份,精母细胞与精细胞比例增加;8月份精母细胞为主.到了9月份,整个精巢完全被精细胞等发育程度较高的精小叶所占据,输精管内充满精液和精荚,为即将到来的交配季节做好准备.三疣梭子蟹交配活动主要集中在10月份.12月份精巢精小叶中出现游离精子.此后,精巢逐渐退化(1-3月),但输精管中一直储存着精液和精荚.三疣梭子蟹精荚形成过程始于前输精细管,精荚膜两层,分别由来自前输精细管分泌的第一种不定物质和其中、后端分泌的第二种不定物质.精荚内的基质可能直接源于精巢的精小叶部分.输精管中的强嗜酸性颗粒与第二种不定物质有融合作用,使输精管中贮存的精荚膜嗜酸性.     

刀额新对虾输精管的组织学及精荚形成

刀额新对虾 (Metapenaeusensis)采自福建沿海 ,体长约 14cm。活体解剖、取样、固定 ,于OlympusBH 2显微镜下观察 ,其生殖管道分为前输精管、中输精管、后输精管和端壶腹 4部分。前输精管上皮为单层柱状上皮 ,其分泌物呈嗜碱性 ;中输精管分泌物为嗜酸性 ,前段为高柱状上皮 ,后段则为柱状上皮 ,至后段共出现 2处上皮隆起 ,隆起间为扁平上皮 ;分泌管出现于中输精管前段 ,其分泌物呈嗜酸性 ,开口于中输精管后段 ,分泌物由此处流入中输精管腔 ;后输精管腔结构与中输精管腔相似 ,但管径缩小 ;端壶腹共分 3个腔 ,其中 2个由后输精管腔延续形成 ,精荚 1个。精荚由精子团和精荚壁组成。精荚壁分 2层 ,内层为均匀的嗜碱性初级精荚壁 ,精子团位于初级精荚壁中央 ;外层为次级精荚壁 ,呈嗜酸性 ,略呈“C”形包被于初级精荚壁之外。整个精荚横切面的外形似柳叶状 ,分为光滑区和皱折区 2部分 ,光滑区由次级精荚壁包被 ,皱褶区则为裸露的初级精荚壁。精荚形成于中输精管后段 ,它是由前输精管的嗜碱性分泌物、中输精管嗜酸性分泌物以及分泌管上皮细胞分泌物经复杂的化学变化形成     

虾夷扇贝雄性生殖系统的组织学研究

１９９７年取材研究了大连长海县的虾夷扇贝的雄性生殖系统的组织结构。虾夷扇贝的精巢构造与栉孔扇贝,贻贝的相似,也是由外膜及其内的无数生殖小管构成。外膜含单层柱状上皮及较厚的肌层。生殖小管间充填着结缔组织及来自外膜的薄层肌肉,结缔组织中含有血管,神经及输精细管。生殖小管由位于基膜上的生殖上皮构成,生殖上皮不断向腔内增殖出精原细胞,初级精母细胞,精细胞及业郛。     

管角螺生殖系统解剖学及组织学观察

解剖并观察了管角螺的生殖系统,采用组织切片技术,对其生殖腺发育及生殖细胞发生过程进行了研究。结果表明,管角螺为雌雄异体,雄性生殖系统主要由精巢、贮精囊、前列腺、输精管和阴茎构成,其中,精巢由生精小管和输精小管组成;根据生精小管内生殖细胞分布和间质细胞数量,精巢发育分为增殖期、生长期(精母细胞分裂期)、成熟与排放期、退化期等4个时期,根据细胞大小、形态及分布特征,精细胞的发生经历了精原细胞、初级精母细胞、次级精母细胞、精子细胞和精子4个阶段。卵巢结构为滤泡型,由滤泡壁和滤泡腔组成,内含嗜酸性颗粒。从卵巢内滤泡的大小、结构及滤泡内嗜酸性颗粒的数量,卵巢发育分为增殖期、生长期、成熟期、排放期和休止期;根据卵细胞的大小、形态及卵黄颗粒的含量,卵细胞发生过程分为增殖期、生长期和成熟期。管角螺生殖腺及生殖细胞的发育均不同步,为多次成熟、多次排放方式。     

条纹锯鮨精子超微结构及其入卵过程的电镜观察

采用扫描和透射电镜技术对自然成熟的条纹锯精子、卵子及精子入卵过程进行观察。观察结果显示,其精子由头部、中段和尾部三部分组成:头部主要由细胞核构成,无顶体结构;中段由线粒体、中心粒复合体(近端中心粒和基体)、袖套组成;尾部主要由轴丝组成,外部包裹质膜,轴丝为典型的"9+2"结构。卵子表面分布纵横交错的网纹,均匀分布着大小不一的微小孔,在卵壳的动物极精孔区的中央有一个受精孔。在授精后10 s即可见到精子通过受精孔进入卵子,刺激卵子发生形态变化封闭受精孔,阻止其他精子入卵,60 s可见受精孔完全封闭。     

西埔湾黄鳍鲷精子发生和形成

本文在超微结构水平上,着重研究了西埔湾黄鳍鲷精子发生和形成过程中各级精细胞形态结构的变化、线粒体和高尔基体等细胞器的演变特点以及精巢内一些体细胞的形态结构与功能。研究结果证实了黄鳍鲷雄性性腺能在半封闭的西埔湾内发育成熟。精子发生和形成可分为原始精原细胞、精原细胞、初级精母细胞、次级精母细胞、精子细胞和精子形成等6个发育阶段。成熟精子由头部、中段和尾部组成,头部近圆形,细胞核呈马蹄形,核内染色质高度浓缩,核上方不具顶体。尾部轴丝为“9×2+2”结构。     

刺参培育池中玻璃海鞘生殖腺组织学的初步研究

2004年2—3月对刺参培育池的玻璃海鞘生殖腺进行组织学观察,结果表明,玻璃海鞘雌雄同体,精巢和卵巢相间排列,两侧生殖管数量不同,右侧4~7条,左侧3条。精巢为分枝状,分散包围在卵巢周围。生殖输送管沿着直肠与肛门相连接,末端开口在围鳃腔中。卵母细胞外有被囊细胞,生殖腺发育可分为4个时期。     

Cell-cell interactions in the testis of the dogfish: stage-related changes in protein synthesis

Previous studies have shown that the testis of Selachians is a very suited model to study stage-dependent changes in Sertoli cells during spermatogenesis (Dubois and Callard 1989; Sourdaine et al. 1990). In the dogfish testis (here: Scyliorhinus canicula), germ cells, at an identical stage of spermatogenesis, are associated with Sertoli cells to form spermatocysts, which are arranged in zones corresponding to the different stages of spermatogenesis. Using previously described methods for the isolation and culture of spermatocysts from four spermatogenic stages (spermatogonia, spermatocytes, early spermatids and late spermatids; Sourdaine and Jégou 1989; Sourdaine and Garnier 1992) and electrophoresis techniques (1D and 2D-SDS-PAGE) we have investigated the [³⁵S] methionine incorporation into proteins in the dogfish testis. Our results indicate that protein synthesis reaches a maximum in spermatocysts with spermatocytes. Marked stage-related changes of protein synthesis and secretion were also observed on the autoradiograms of 1D and 2D-SDS-PAGE. Further investigations of the paracrine control of germ cells on Sertoli cell protein synthesis requires the identification of specific Sertoli cell proteins in the dogfish.     

Gonadal development in early life stages of <Emphasis Type="Italic">Spratelloides gracilis</Emphasis>

ABSTRACT:   The gonad of Spratelloides gracilis was not sexually differentiated in the yolk-sac, preflexion, flexion and postflexion stages. Sexual differentiation and development of the ovary and testis started in the transition stage from larva to juvenile. In juveniles at the fin ray completion stage, the ovary and testis could be distinguished because the ovary contained germ cells initiating meiosis and the testis had blood vessels and a high density of somatic cells. The ovary further developed in larger juveniles to have oocytes of perinucleolus stage together with those of the chromatin nucleolus stage, and oogonium. However, in the testis of larger juveniles, primary spermatogonium began proliferation by meiosis. Sexual differentiation may be regarded as one of morphological and functional changes accompanying metamorphosis in S. gracilis . Some fish larger than the mature size of 60 mm standard length had advanced germ cells and functional gonads, others did not have functional gonads. The distal end of the immature gonads did not connect with a genital duct near the anus. These observations indicate that S. gracilis has large variability in size-at-maturity. The variability in size-at-maturity in S. gracilis , together with large variability in age-at-maturity, may constitute an ecological basis for an extended spawning season in S. gracilis .     

外源性促性腺激素诱导日本鳗鲡精子发生和成熟的作用机制

用兔抗血清对抗促黄体素生成素受体（LHR）或称绒毛膜促性腺激素受体（CGR）和雄激素受体（AR）进行LHR和AR免疫组织化学定位,以揭示外源性促性腺激素（鲤脑垂体激素和hCG）诱发日本鳗鲡精子发生及其内分泌机制。结果表明，经过注射激素处理后的实验组与注射前的对照组相比较，其精巢发育和精子发生出现十分显著的变化。组织学切片观察显示,激素处理前鳗鲡精巢处于精原细胞增殖期，而两种激素混合注射后第10天，实验组可见精小叶中精原细胞的有丝分裂和初级与次级精母细胞的数量显著的增加。注射后第35天，靠近生殖上皮除有少量精原细胞外，精小叶中有大量初级精母细胞和次级精母细胞和少数精子细胞以及管腔中存在少量精子。在注射后第83天，日本鳗鲡完成了精子发生和精巢发育成熟以及释精。免疫组织化学染色结果进一步揭示，激素处理前，LH受体免疫活性分布在生殖上皮，显示强的免疫阳性反应；激素处理后，LH受体定位在Sertoli细胞和间质细胞以及精原细胞和初级与次级精母细胞的胞膜上，均显示强的免疫阳性反应。激素处理前，雄激素受体定位在生殖上皮和早期生精细胞的胞膜上；激素处理后，AR则定位在这些生精细胞的核或胞质，而精子细胞和精子显示免疫阴性反应。这些结果首次证明了这两种激素诱导鳗鲡精子发生和成熟的作用机制是通过LH受体和雄激素受体的介导。     

Immunohistochemical localization of rainbow trout androgen receptors in the testis

SUMMARY: We examined the distribution of two rainbow trout androgen receptors (rtAR: rtAR-α and rtAR-β) in the testis immunohistochemically using a specific antibody to clarify the target cells of androgen in spermatogenesis. Positive rtAR immunoreactivity in paraffin-embedded sections was revealed using microwave treatment, and was detected in the nuclei of Sertoli cells, Leydig cells, and other interstitial cells. The presence of rtAR in Leydig cells suggested that fish androgens regulate Leydig cell activity in an autocrine fashion similar to mammalian androgens. In addition, we found that not all Leydig cells exhibited rtAR immunoreactivity in the mature testis by double staining using anti-3β-hydroxysteroid dehydrogenase (3β-HSD) antibody. Furthermore, rtAR immunoreactivity was also detected in the nuclei of spermatogonia, spermatocytes, and spermatids. The intensity of rtAR immunoreactivity in the nuclei of spermatogonia seemed to be weaker than those of spermatocytes and spermatids. These results suggested that androgens act directly on both germ cells and somatic cells in the regulation of spermatogenesis in the rainbow trout.     

Spermatogenesis in teleost: insights from the Nile tilapia (Oreochromis niloticus) model

The morphometric study of spermatogenic cysts in sexually mature tilapias, during the evolution of spermatogenesis, showed a dramatic increase in both number of germ cells and cyst volume. However, the opposite trend was observed for germ cell size. Nevertheless, the number of Sertoli cells increased gradually up to leptotene/zygotene cysts, stabilizing thereafter. Based on the number of spermatids supported by each Sertoli cell and compared to mammals, Sertoli cell efficiency in tilapias is remarkably high. Sertoli cell proliferation was frequently observed, mainly in spermatogonial cysts, and probably is the major factor related to the testis growth and the increase in sperm production that normally occurs in adult tilapias. The combined duration of spermatocytes (5 days) and spermiogenic (5–6 days) phases of spermatogenesis in fish kept at 25 °C was 10–11 days. Mainly due to acceleration in meiosis, these two phases lasted a total of 6 days in tilapias kept at 30 °C, in the opposite way, at 20 °C spermatogenesis was arrested at pachytene spermatocytes. To our knowledge, this is the most comprehensive investigation performed up to date on testis morphometry and function in adult tilapias.     

尼罗罗非鱼Smoothened的鉴定、表达模式及在精巢中的作用

为探究Smoothened (Smo)信号在精巢不同细胞增殖与存活中的作用,实验分离鉴定了尼罗罗非鱼smo (命名为Onsmo),检测了其在不同组织中的表达分布及在精巢中的细胞表达模式,在尼罗罗非鱼精巢组织的体外培养体系中,用Smo特异性激动剂SAG或抑制剂环巴胺分别进行处理,EdU掺入法及TUNEL法检测了处理后生殖细胞(Vasa⁺)、Sertoli细胞(Amh⁺)与Leydig细胞(Cyp17a1⁺)增殖或凋亡情况。结果显示,Onsmo开放阅读框全长2 478 bp,编码825个氨基酸,含有7次跨膜结构域,与人SMO氨基酸一致性达77%;Onsmo表达于包括精巢在内的多个组织;在精巢中,Onsmo在多种不同类型细胞表达,包括精原细胞、精母细胞、Sertoli细胞以及Leydig细胞;在精巢组织的体外培养体系中,SAG处理对精原细胞增殖具有显著促进作用,而环巴胺处理对Sertoli细胞、Leydig细胞凋亡具有显著促进作用。研究表明,On Smo信号在尼罗罗非鱼精巢精原细胞增殖与体细胞存活中具有重要作用。该研究首次证实...     

Gonadal morphogenesis and sex differentiation in cultured chub mackerel,Scomber japonicus

The timing of primordial germ‐cell (PGC) migration with regard to the gonadal anlagen, gonad formation and sex differentiation was examined histologically in the chub mackerel (Scomber japonicus) at 5–190 days post hatching (dph). At 5 dph, PGCs appeared on the peritoneal epithelium surface or in the mesentery, on the dorsal side of the abdominal cavity. By 10 dph, stromal cells around the PGCs proliferated. The gonadal primordium was formed by 15 dph. The gonadosomatic index was 0.01% at 30 dph and increased thereafter (0.32% in females and 0.04% in males at 160 dph). Ovarian differentiation occurred at 30–40 dph, indicated by ovarian cavity formation (elongation and fusion of the upper and lower ovarian edges). Meiosis was subsequently initiated. A few meiotic oocytes surrounded the cavity at 50 dph; most were in the perinucleolus stage at 60 dph and attained a diameter of 60–70 μm at 190 dph. Testicular differentiation occurred at 30 dph, indicated by the formation of the sperm duct primordium. Spermatogonia gradually proliferated, developing into spermatocytes at the chromatin–nucleolus stage (after 90 dph) and subsequently into spermatids and spermatozoa (160 dph). These data could aid the development of seeding and cell‐engineering technologies for scombrid fish.     

感染白斑综合症病毒中国对虾雄性生殖系统的PCR检测与电镜观察

通过人工投喂携带WSSV的毒饵，对性腺发育成熟的中国对虾（Fenneropenaeus chinensis）雄虾（♂）进行感染实验。采用nest-PCR（巢式PCR）技术，检测感染后的中国对虾雄性生殖系统受WSSV感染情况，同时选取感染严重的虾样进行电镜观察。巢式PCR检测结果表明，感染组中国对虾的精巢、输精管和精囊均被WSSV感染，其中精囊呈阳性的最多，输精管次之，精巢最少。通过电镜进一步观察发现，WSSV粒子只存在于精巢、输精管和精囊的结缔组织中，而在其他组织和生殖细胞中均未发现病毒粒子。其中，精巢中WSSV粒子存在于精巢内两个生精小管之间的结缔组织；输精管中WSSV粒子存在于管壁的结缔组织；精囊中WSSV粒子也只存在于精囊内膜的结缔组织和精荚膜的结缔组织中。PCR检测和电镜观察结果均表明，WSSV粒子能感染中国对虾的雄性生殖系统且对性腺感染存在着一定的组织特异性。