Neuropeptidergic control of Octopus oviducal gland

The oviducal gland of the female of Octopus vulgaris lies about halfway along the oviduct. Progesterone and 17beta-estradiol receptors have been immunolocalized in the nuclei of the cells of the glandular compartment of previtellogenic glands. We also have evidence of FMRFamide-like and cGnRH-I-like immunoreactivity in the nerve endings that reach the oviducal gland. Moreover, we have recently shown APGWamide immunoreactivity in the glandular cells of the inner part of the oviducal gland. Here we report a review on these findings as well as our latest studies on the effect that neuropeptides may exert on the secretory activity of the oviducal gland. cAMP seems to be a possible second messenger involved in such a process. We discuss the findings of a neuropeptidergic action on the glandular cells of oviducal gland in a more complex frame of molecules, such as steroids, biogenic amines and neuromodulators, controlling the activity of the gland.     

The presence of APGWamide in Octopus vulgaris: a possible role in the reproductive behavior

The concerted action of many neuropeptides has been implicated in the nervous control of specific behaviors in many molluscs. In the present study, the presence of amidated tetrapeptide Ala-Pro-Gly-Trp-NH2 (APGWamide) in those lobes that are involved in the control of reproductive behavior in Octopus vulgaris has been investigated. APGWamide immunoreactivity was mainly confined to the posterior olfactory lobule and in the inferior frontal system. These areas are involved in Octopus in the processing of either chemotactile sense or olfaction. From these lobes, immunoreactive fibers reached other lobes of the central nervous system (CNS) which could be indirectly involved in the reproductive behavior. APGWamide immunoreactivity was also present in the glandular cells of the oviducal gland in the female reproductive system. These results constitute the first detailed immunolocalization of APGWamide in cephalopods and open a new insight into the possible effects that both distant and close chemical stimuli can exert on neuropeptidergic circuitries, which may affect the reproductive behavior of cephalopods.     

A estradiol-17beta receptor in the reproductive system of the female of Octopus vulgaris: characterization and immunolocalization

In this study, for the first time we have identified an estradiol-17beta receptor (ER) in the reproductive system of the female of Octopus vulgaris. Scatchard analysis revealed that one binding component with high affinity and low capacity for the ligand was present in the cytosol, but not in the nuclear extract of the ovary and the oviduct. A steroid specificity competition assay showed that 3H-estradiol-17beta binding activity showed a preference for estradiol-17beta. DNA-cellulose chromatography confirmed the presence of one 3H-estradiol-17beta binding component. By using antibodies anti ER (578-595), we have localized by Western blotting one band of about 70 kDa. ER immunoreactivity has been localized in the nuclei of the follicle cells of the ovary, in the nuclei of the epithelium lining the proximal portion of the oviduct and in the nuclei, and in the cytoplasm of the inner region of the oviducal gland and in the cytoplasm of the outer region of the oviducal gland. These data, taken together, provide evidence that in Octopus vulgaris the ER has biochemical and immunohistochemical characteristics resembling those of ER in vertebrates.     

平疣桑椹石磺生殖系统结构及精子储存场所

雌雄同体贝类精子的储存和利用规律一直是国内外贝类生物学研究的难点之一,本文利用活体解剖、显微观察、组织切片和扫描电镜技术,综合研究了平疣桑椹石磺(Platevindex mortoni)的生殖系统及精子储存场所。结果显示,其生殖系统包括生殖器本部、雌性生殖部分和雄性生殖部分。生殖器本部由两性腺、两性输送管、蛋白腺、黏液腺、支囊组成;雌性生殖部分包括输卵管、受精囊、阴道,位于身体中后方体腔内;雄性生殖部分包括输精管、刺激器、阴茎、阴茎鞘和阴茎牵引肌,位于身体前端右侧体腔内;其阴茎有阴茎鞘,阴茎表面布满倒刺。平疣桑椹石磺阴茎为直线状,无雄性附属腺。未交配的性成熟个体支囊内充满细长精子,受精囊内无精子;而交配后充当雌性个体的支囊内均为细长的自体精子,受精囊内有大量活力较强的粗短精子,其支囊为自体精子的存储场所,而受精囊为异体精子的存储场所。其精子储运情况为:两性腺内精子成熟后暂存于支囊,交配时通过输精管运输至阴茎,由阴茎输送精子至对方的阴道,异体精子进入受精囊内存储待用。     

A histological study of the accessory reproductive organs of female Loligo forbesi (Cephalopoda: Loliginidae)

In Loligo forbesi Steenstrup, the female reproductive system consists of the ovary and accessory reproductive organs which include the oviducal gland, the nidamental gland, the accessory nidamental gland and seminal receptacle. Histological studies were made on the accessory reproductive organs of female L. forbesi. The various changes observed during maturation are described and the functional significance discussed. The secretions produced by the oviducal gland and nidamental gland apparently form the egg coats. The seminal receptacle serves to store spermatozoa after mating. The function of the accessory nidamental gland is unknown.     

Antigenic homogeneity of male Müllerian gland (MG) secretory proteins of a caecilian amphibian with secretory proteins of the mammalian prostate gland and seminal vesicles: evidence for role of the caecilian MG as a male accessory reproductive gland

Whereas in all other vertebrates the Müllerian ducts of genetic males are aborted during development, under the influence of Müllerian-inhibiting substance, in the caecilian amphibians they are retained as a pair of functional glands. It has long been speculated that the Müllerian gland might be the male accessory reproductive gland but there has been no direct evidence to this effect. The present study was undertaken to determine whether the caecilian Müllerian gland secretory proteins would bear antigenic similarity to secretory proteins of the prostate gland and/or the seminal vesicles of a mammal. The secretory proteins of the Müllerian gland of Ichthyophis tricolor were evaluated for cross-reactivity with antisera raised against rat ventral prostate and seminal vesicle secretory proteins, adopting SDS-PAGE, two-dimensional electrophoresis and immunoblot techniques. Indeed there was a cross-reaction of five Müllerian gland secretory protein fractions with prostatic protein antiserum and of three with seminal vesicle protein antiserum. A potential homology exists because in mammals the middle group of the prostate primordia is derived from a diverticulum of the Müllerian duct. Thus this study, by providing evidence for expression of prostatic and seminal vesicle proteins in the Müllerian gland, substantiates the point that in caecilians the Müllerian glands are the male accessory reproductive glands.     

嘉庚蛸雌性生殖系统组织学观察

对象山港自然海区中的嘉庚蛸(Octopus tankahkeei)雌性生殖系统的组织学结构进行了研究.结果表明,雌性生殖系统由卵巢、输卵管、输卵管腺组成.卵巢单个、球形,内包裹滤泡细胞围成的卵子,输卵管1对,开口于外套腔中部,每条输卵管中部膨大形成圆球状的输卵管腺.近端输卵管内具两瓣蘑菇状突起,上有不规则短指状分枝,突...     

Sperm morphology of the neotropical harvestman Iporangaia pustulosa (Arachnida: Opiliones): comparative morphology and functional aspects

We describe herein the sperm morphology of the harvestman Iporangaia pustulosa. Adult males were dissected, the reproductive tract was schematized and the seminal vesicle was processed by light, transmission and scanning electron microscopy. The male reproductive tract is composed of a tubular testis, two deferent ducts, a seminal vesicle, a propulsive organ and a penis, similar to that observed in other Opiliones. The spermatozoa from the seminal vesicle are oval, aflagellate and immotile, presenting a nucleus surrounding an invagination of the cytoplasm, as well as a complex acrosome and projections on the cell surface. In the testis, spermatozoa are devoid of projections. In the seminal vesicle, they gradually acquire the projections with tufts adhering to it. Consequently, spermatozoa in various distinct stages of projection development can be found in the seminal vesicle. We believe that these projections (1) could help transport sperm along the male and perhaps female reproductive tracts; (2) are used to anchor the spermatozoa inside the female spermatheca in order to avoid mechanical displacement by the genitalia of other males and (3) may play a role in oocyte recognition. We propose that the evolution of aflagellarity in Opiliones is related to the unique morphology of the female reproductive tract. Since eggs are fertilized on the tip of the ovipositor just prior to being laid, there is no advantage favoring sperm mobility. Additionally, female sperm receptacles are small and males that produced small spermatozoa would have a higher chance of fertilizing more eggs.     

Female mating receptivity after injection of male-derived extracts in Callosobruchus maculatus

The effects of male-derived extracts on female receptivity were investigated in Callosobruchus maculatus (Coleoptera: Bruchidae). Injection of aqueous extracts of the male reproductive tract into the abdomen of females reduced receptivity. Aqueous extracts of male reproductive tracts were divided to three molecular weight (MW) fractions by ultrafiltration: Fractions: (I) MW<3 kDa, (II) 3-14 kDa, and (III)>14 kDa. Fraction II reduced female receptivity from 3h after injection, and Fraction III reduced female receptivity from 2 days after injection. On the other hand, no effect on receptivity was found for Fraction I. Furthermore, male reproductive tract organs were divided into accessory gland, testis, and seminal vesicle including the ejaculatory duct. Aqueous extracts of the seminal vesicle reduced receptivity of females immediately following injection, while aqueous extracts of the accessory gland reduced receptivity at the second day. The results suggest that the components of Fraction II existed in the seminal vesicle, and those of Fraction III in the accessory gland. The results of the present and the previous studies in Callosobruchus chinensis, a species closely related to C. maculatus, were compared and are discussed from the viewpoint of the significance of ejaculation in the two species.     

Microanatomy of the male and female reproductive tracts in the long‐tailed butterfly ray Gymnura poecilura,an elasmobranch with unusual characteristics

The anatomy of the male and female reproductive systems was investigated in the long‐tailed butterfly ray Gymnura poecilura using gross observation and light microscopy. The testes are highly asymmetrical, to the extent that only the left testis is functional and the right testis is completely absent. Both of the male genital ducts are present and symmetrical, although spermatozoa only occur in the left duct. The genital ducts are straight and unconvoluted, with regular incomplete internal partitions throughout. Females do not possess a right ovary, nor do the oviducal glands exhibit distinct club and papillary zones, and the baffle zone lacks baffle plates. In all sections of the gland, the tubules display different secretory activities depending on the proximity to the gland lumen. The gland produces a thin egg membrane that encases each egg individually, while the endometrium is formed into trophonemata.     

Sex steroid hormone fluctuations and morphological changes of the reproductive system of the female of Octopus vulgaris throughout the annual cycle

Sex steroids (17beta-estradiol and progesterone) and morphological variations of the reproductive system of the female of Octopus vulgaris from the Bay of Naples were followed over a period of 2 years. The increase in the ovary weight was independent of body weight as demonstrated by the gonado-somatic index (GSI). Both 17beta-estradiol and progesterone have been detected in the ovary of O. vulgaris, and their concentrations changed in correlation with the ovarian development. No 17beta-estradiol or progesterone was found in the hemolymph. 3beta-Hydroxysteroid dehydrogenase activity has been detected in the ovary, indicating that in the female of O. vulgaris the reproductive system is a source of sex steroid hormones. According to the morphological changes of the ovary, the ovarian cycle can be divided into the following phases: previtellogenesis; early vitellogenesis, full vitellogenesis and late vitellogenesis. The morphological changes of the oviducts and oviducal glands throughout the reproductive cycle were in accordance with their role in the transport and secretion of gelatinous coat covering the eggs, as well as in sperm storage and sperm reactivation during fertilization. J. Exp. Zool. 289:33-47, 2001.     

Optic gland implants and their effects on the gonads of Octopus.

1. Optic glands transplanted from one Octopus vulgaris into another cause enlargement of the gonads and ducts of the recipient. 2. Enlargement occurs whether or not the gland was secreting when implanted and regardless of the sex of the donor or recipient. 3. Glands derived from Eledone moschata or Octopus macropus implanted into O. vulgaris are as effective as glands derived from O. vulgaris. 4. Implants derived from Sepia officinalis or Loligo vulgaris appear to be ineffective.     

长蛸生殖系统的形态学与组织学观察

运用解剖学和组织学方法对长蛸(Octopus variabilis)生殖系统的形态结构进行了研究.结果表明,长蛸雌雄异体并异形,雄性右侧第三腕茎化.长蛸雌性生殖系统由一个卵巢、成对的输卵管及输卵管腺组成.卵巢壁上发出一条线状具分支的生殖索,米粒状的滤泡以卵柄连接至生殖索上.每个滤泡是由单层滤泡细胞围绕着一个卵母细胞构成.输卵管形成丰富的纵行褶皱,黏膜上皮具有纤毛.输卵管腺含有两种类型腺细胞.雄性生殖系统包括精巢、输精管前段、储精囊、摄护腺、盲囊、输精管后段和精荚囊.精巢内部被结缔组织分隔成许多精小叶,精原细胞由小叶壁中的生殖上皮产生,并向小叶腔中逐步分化成精子.输精管前段、盲囊和摄护腺所分泌的黏液物质共同参与精荚的形成.储精囊和输精管后段形成较多的纵行褶皱,输精管后段上皮游离面的纤毛可运输生殖细胞.精荚囊的作用则是贮存精荚,囊壁中的平滑肌利于长蛸交配时精荚的排出.     

Female mating receptivity inhibited by injection of male-derived extracts in Callosobruchus chinensis

The effects of male-derived extracts on female receptivity to remating were investigated in Callosobruchus chinensis (Coleoptera: Bruchidae). Injection of aqueous extracts of male reproductive tracts into the abdomen of females reduced receptivity. When aqueous extracts of male reproductive tracts were divided to three molecular weight (MW) fractions by ultrafiltration: <3, 3-14, and >14 kDa, the filtrate containing MW substances <3 kDa reduced female receptivity 3h and 1 day after injection, whereas the fraction containing MW substances >14 kDa inhibited receptivity 2 and 4 days after injection. Finally, male reproductive tract organs were divided into accessory gland, seminal vesicle, and testis. Aqueous extracts of testis reduced receptivity of females on the second day and at 3h, and aqueous extracts of accessory gland reduced receptivity of females on the second day after injection. On the other hand, aqueous extracts of seminal vesicle did not reduce female receptivity. The results indicate that more than one mechanism may be involved in producing the effects of male-derived substances on female receptivity; low MW male-derived substances, which possibly exist in testis, cause short-term inhibition, while high MW substances, which possibly exist in the accessory gland, inhibit female mating later than low MW substances in C. chinensis.     

Ultrastructure of the male reproductive organs in the interstitial annelid Sphaerosyllis hermaphrodita (”Polychaeta”, Syllidae)

 The reproductive organs of the simultaneous hermaphrodite Sphaerosyllis hermaphrodita (Syllidae, Exogoninae) were examined by TEM and reconstructed from ultrathin serial sections. Oocytes are produced in the 11–13th chaetigerous segments and then attached to the outer body surface. The male organs comprise a seminal vesicle, testes, sperm ducts and copulatory chaetae. The unpaired seminal vesicle is an uncompartmented cavity above the gut and within the chaetigerous segments 8–10. Its interior is lined with a layer of gland cells that degenerate as spermatogenesis in the vesicle proceeds. The testes are situated ventrolaterally, close to the seminal vesicle in the 9th chaetigerous segment. They contain cells at early stages of spermatogenesis, which are connected to one another by zonulae collares. The testes and seminal vesicle are enclosed in epithelia. Paired sperm ducts run ventrally from about the midline of the body under the seminal vesicle and into the parapodia of the 9th chaetigerous segment. There they open, together with the protonephridia of this segment, to the outside next to the stout copulatory chaeta. Each sperm duct consists of six cells, the luminal surface of which bears microvilli but no cilia. Only in animals with fully differentiated sperm does the small opening of the proximal duct cell in each duct give access to the seminal vesicle. The mode of sperm transfer is discussed. Accepted: 9 December 1996     

Comparative studies of testicular structure and sperm morphology among copulatory and non-copulatory sculpins (Cottidae: Scorpaeniformes: Teleostei)

Testicular structure of 9 species and sperm head morphology of 19 species of Cottidae were observed in order to clarify relationships between morphological characteristics of the male reproductive organ and reproductive mode (copulation or non-copulation). Morphological structure of the testis was divided into the following five types based on the sperm transfer and reservoir system: (1) a non-duct type in which the sperm duct is not a distinct exterior structure, but the tube for sperm transport traverses along the testis as an interior structure; (2) an anterior duct type with distinct anterior sperm ducts traversing along the testis; (3) a posterior duct type with distinct anterior sperm ducts traversing along the dorsal hilus of testis and posterior sperm ducts extending to the rear of the testis; (4) an anterior duct posterior vesicle type with distinct anterior sperm ducts traversing along the testis, and the right and left sperm ducts fusing in the rear of testis, forming the seminal vesicle; (5) a non-duct posterior vesicle type in which sperm ducts do not accompany the testis, and the testis and seminal vesicle are connected directly or through posterior sperm ducts. It is thought that in Cottidae the non-duct type of reproductive organ is primitive, and the anterior duct type is common to all non-copulating species. The testes and accompanying seminal vesicle were seen only in copulating species. Sperm head morphology was divided into three types according to the length/width ratio: oval type ≤2, intermediate type >2 and ≤3, and slender type >3. The type of sperm head corresponded closely to the reproductive mode; non-copulating species had oval sperm head, and copulating species had intermediate or slender ones. These results suggest that the structure of the testis and the morphology of the sperm head evolved from testes with anterior sperm ducts and oval sperm heads to testes with an associated seminal vesicle and slender sperm heads in association with the evolution from non-copulatory to copulatory reproduction in Cottidae.     

3种蛾类雄性内生殖系统形态学研究

为了探究蛾类昆虫新的有效分类特征,本研究对直脉青尺蛾Geometra valida、白雪灯蛾Chionarctia niveus和多斑豹蠹蛾Zeuzera multistrigata雄性内生殖系统进行了解剖观察和形态学比较。结果表明：3种蛾类雄性内生殖系统均由精巢、贮精囊（前贮精囊和后贮精囊）、输精管、复射精管、单射精管（单射精管原节和单射精管表皮节）和附腺组成;种间形态差异表现在贮精囊的形状及连接方式、复射精管的形状及长短、单射精管和附腺的长度等方面,这些鉴别特征可为蛾类分类及系统发育研究提供形态学借鉴。     

Elucidation of the protein composition of mouse seminal vesicle fluid

The seminal vesicles are male accessory sex glands that contribute the major portion of the seminal plasma in which mammalian spermatozoa are bathed during ejaculation. In addition to conveying sperm through the ejaculatory duct, seminal vesicle secretions support sperm survival after ejaculation, and influence the female reproductive tract to promote receptivity to pregnancy. Analysis of seminal vesicle fluid (SVF) composition by proteomics has proven challenging, due to its highly biased protein signature with a small subset of dominant proteins and the difficulty of solubilizing this viscous fluid. As such, publicly available proteomic datasets identify only 85 SVF proteins in total. To address this limitation, we report a new preparative methodology involving sequential solubilization of mouse SVF in guanidine hydrochloride, acetone precipitation, and analysis by label-free mass spectrometry. Using this strategy, we identified 126 SVF proteins, including 83 previously undetected in SVF. Members of the seminal vesicle secretory protein family were the most abundant, accounting for 79% of all peptide spectrum matches. Functional analysis identified inflammation and formation of the vaginal plug as the two most prominent biological processes. Other notable processes included modulation of sperm function and regulation of the female reproductive tract immune environment. Together, these findings provide a robust methodological framework for future SVF studies and identify novel proteins with potential to influence both male and female reproductive physiology.     

Ultrastructure of the copulatory organ of Haplopharynx quadristimulus and its phylogenetic significance (Plathelminthes,Haplopharyngida)

Summary The male reproductive system in Haplopharynx quadristimulus consists of paired testes, sperm ducts, seminal vesicles, seminal ducts, a copulatory organ containing prostatic vesicle and stylet apparatus, and the male canal. By electron microscopy all components appeared to be regional specializations of a canal extending from the testes to the body wall and lined by a multiciliated epithelium. The epithelium of the stylet apparatus contained six different cell types. One cell type (matrix syncytium) formed the stylet and the other five were located distal to the stylet/prostatic-vesicle junction along the male system epithelium. Each cell type was attached to the supporting intercellular matrix at a different level along the stylet apparatus. All cell types extended to the distal end of the stylet apparatus regardless of where they originated along its length. The cells in the apparatus lacked cilia, but one of the cell types contained rootlets. Modified rootlets or rootlet derivatives were possibly present in another cell type in the form of rootlet-like ribbons. The findings support the monophyly of the Macrostomida Haplopharyngida (by common occurrence of a matrix syncytium) and at the same time suggest their separation as two distinct taxa (by differences in the structure of the prostatic vesicle and other parts of the stylet apparatus).Abbreviations a accessory spine - c circular muscle - ce centriole - ci cilium - di dictyosome - e epithelial cell - ed ejaculatory duct - ep epidermal cell - f rootlet-like ribbon - g prostatic gland cell neck - g1 type I gland cell granules - g2 type II gland cell granules - g3 type III gland cell granules - h hemidesmosome - i intercellular matrix - im internal muscle - j septate junction - l stylet apparatus lumen - le spine lateral extension - lm longitudinal muscle - m matrix syncytium - mc male-canal epithelial cell - me male canal - mp male pore - mt microtubules - mv microvilli - n nucleus - nc nerve cell body - np nerve process - om oblique muscle - p prostatic vesicle epithelial cell - pv prostatic vesicle - r rootlet - s stylet - sa stylet apparatus - sc sensory receptor - sd sperm duct - se seminal duct - sl stylet lumen - sp spot desmosome - sr sperm - sv seminal vesicle - t terminal web - te testis - u ultrarhabdite - z zonula adhaerens - 2 cell type 2 - 3 cell type 3 - 4 cell type 4 - 6 cell type 6