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...     

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.     

Progesterone receptor in the reproductive system of the female of Octopus vulgaris: Characterization and immunolocalization

In this study for the first time we have characterized a progesterone receptor 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 only in the nuclear extract. Competition experiments showed that the progesterone receptor was strictly specific for progesterone. DNA-cellulose binding and DEAE-Sephacel both confirmed the presence of one ³H-progesterone binding component which eluted at a salt concentration of 0.14 ± 0.05 M NaCl and 0.15 ± 0.05 M NaCl respectively. By using monoclonal antibodies against chicken progesterone receptor (subunits A and B), we have localized on Western Blot one band of about 70 kDa. Immunoreactivity for progesterone binding molecules has been localized in the nuclei of the follicle cells of the ovary, of the proximal portion of the oviduct and of the outer region of the nidimental gland. These data, taken together, provide evidence that in Octopus vulgaris the progesterone receptor has biochemical and immunohistochemical characteristics resembling those of progesterone receptor in vertebrates. Mol. Reprod. Dev. 50:451–460, 1998. © 1998 Wiley-Liss, Inc.     

Presence of two neuropeptides in the fusiform ganglion and reproductive ducts of Octopus vulgaris: FMRFamide and gonadotropin-releasing hormone (GnRH)

We have found evidence of FMRFamide-like and cGnRH-I-like immunoreactivity in the central nervous system (CNS) and in the reproductive ducts of both female and male cephalopod Octopus vulgaris. Cell bodies and fibers were immunolocalized in the fusiform ganglion from which the nerves that reach the female and male reproductive ducts arise. FMRFamide-like and cGnRH-I-like immunoreactive nerve endings were present in the oviduct, and in the oviducal gland of the female and in the seminal vesicle of the male. The GnRH-like peptide from the reproductive ducts has been partially characterized by HPLC. The retention time of the Octopus vulgaris GnRH-like peptide was similar to the retention time of cGnRH-I. Based on these observations we suggest that FMRFamide-like and a novel GnRH-like peptide are involved in the control of reproductive ducts of Octopus vulgaris. One possibility is that the peptides affect gamete transport. Another possibility is that they regulate secretory products such as mucus and mucilaginous substances from the oviducal gland and the seminal vesicle. Our data provide further evidence to support the hypothesis of the existence of a central and peripheral peptidergic control of reproduction of Octopus vulgaris.     

Specificity of inhibition by steroids of porcine oocyte maturation in vitro.

In order to examine the influence of several steroids on the process of oocyte maturation, denuded (adherent cumulus granulosa cells mechanically removed) and intact (cumulus granulosa cells left attached) porcine oocytes were cultured in the presence or absence of estradiol-17 beta, estradiol-17 alpha, testosterone, cortisol, progesterone, or the nonsteroidal estrogen diethyl stilbestrol (all at 10 microgram/ml) in defined medium that contained either BSA or dextran. Estradiol-17 beta was the only steroid to exert a significant inhibitory effect on the maturation of denuded oocytes, and did so only in BSA supplemented medium. The inhibition was reversible in that oocytes, cultured in steroid-free medium after initial culture in estradiol-17 beta medium, resumed meiotic maturation. Oocytes took up 3H-estradiol-17 beta in both media, although less radiolabel entered oocytes in BSA supplemented medium. The majority of label in the oocytes, when cultured with either medium, was not displaced by excess radioinert estradiol-17 beta or progesterone, nor were the oocytes saturated even when cultured in 10(-6) M estradiol-17 beta. Autoradiography of sectioned oocytes after culture in 3H-estradiol-17 beta has shown that there was no selective accumulation of silver grains over the germinal vesicle as was the case with granulosa cell nuclei. This observation suggests that estradiol-17 beta may not act at the level of the oocyte nucleus.     

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.     

The relationship among ovarian condition, steroid hormones, and estrous behavior in Anolis carolinensis

The lizard Anolis carolinensis ovulates a single egg alternately from each ovary every 14 days. The ovulated egg enters the ipsilateral oviduct, acquires a shell, and is oviposited 18 or 19 days later. Thus, there is only a single egg in one of the oviducts (one-egg condition) during most of the estrous cycle, but there is a 4-5 day period when a mature, shelled egg is in one oviduct while a recently ovulated egg is in the contralateral oviduct (two-egg condition). Analysis of ovarian follicular diameters indicates that the largest follicle in a single ovary exhibits a growth spurt about halfway through its 28-day vitellogenic growth phase. The corpus luteum, once formed from the ovulated follicle, exhibits a linear decrease in weight, becoming fully regressed just before oviposition of the egg in the ipsilateral oviduct. Plasma concentrations of estradiol-17 beta and progesterone are high in two-egg animals. After oviposition, plasma concentrations of progesterone are still high in one-egg animals whereas those of estradiol-17 beta are much lower. These ovarian and hormonal changes during the estrous cycle are discussed in relation to the probable sources of estradiol-17 beta and progesterone, the control of the alternating pattern of ovulation and oviposition, and the role of steroid hormones in female sexual receptivity in this species.     

Effect of estrogens on glucose phosphate dehydrogenase activity of liver and oviduct in the amphibian Bufo arenarum.

Glucose- 6phosphate dehydrogenase (G-6PDH) stimulation by estradiol- 17beta has been studied in oviduct and liver of Bufa arenarum. OviducalG-6PDH has been found to be stimulated by a single dose of estradiol- 17beta (100 mug/100 g body weight), the stimulation being dependent on season. Hepatic G-6PDH of females is susceptible to hormonal stimulation, without seasonal variation, while in males the enzymatic activity is not modified under the same conditions. The stimulating effect of estrogen on oviducal and hepatic G- 6PDH was inhibited by Actynomicin D. The susceptibility of G- 6PDH to estrogenic action would assure NADPH production, indispensable for the biosynthesis of lipids which are required for cell growth and for hepatic vitellogenesis.     

Isolation and characterization of an estrogen binding protein which may integrate the plethora of estrogenic actions in non-reproductive organs

A putative estrogen receptor (pER) from mouse liver has been characterized. The heterodimer protein (81–84 kDa) consists of two covalently bound subunits (61–67 and 17–27 kDa) with following characteristics: sedimentation constant — 4.9 S; IP — 4.8; dissociation constant (K_d) for estradiol-17β binding — 0.7 nmol; binding sites — 0.746 pmol/mg protein; relative binding affinity — estradiol-17β — 100, estrone — 80 and estriol — 30; specificity — does not bind, other natural steroids, synthetic estrogens, antiestrogens and bioflavonoids. Importantly, immunosuppressants, neuroleptic and carcinogens influence ³H-estradiol-17β binding to pER. Interestingly, pER is a serine phosphatase and this may have relevancy to estrogen action in Alzheimer's disease. The polyclonal anti-pER antibody does not react with estrogen receptors (ER). ER antibody does not react with pER. Remarkably, anti-pER antibody reacts with calcineurin, a brain phosphatase and anti-calcineurin antibody reacts with pER. Immunohistochemical analyses showed that pER is undetectable in reproductive organs (except ovary). It is localized on the plasma or the nuclear membranes in some, in cytoplasm and/or nucleus in other cells of non-reproductive organs (skeletal, neural, vascular, hair and retina), and in tumors (mammary, endometrial and prostate cancers, and prostatic hyperplasia). The information presented justifies the proposition that pER may mediate the estrogenic actions in non-reproductive organs.     

Uptake and effects of ovarian steroids in the early pig embryo: In vitro and in vivo studies

The role of ovarian steroids in the preimplantation pig embryo was studied in vivo and in vitro. Twenty gilts were treated three times daily on days 1 to 4 after insemination with either 25, 100, 250, or 1000 mg progesterone in oil, and 17 gilts were injected with corresponding amounts of sesame oil (controls). All gilts were slaughtered 5 days after insemination and the embryos were recovered. Oviduct and plasma progesterone content were significantly (P<0.001) higher in gilts treated with 750 mg of exogenous progesterone per day. After 750 mg progesterone, oviduct progesterone content was twice as high as control levels, while after 3000 mg progesterone per day the levels in oviduct and uterus exceeded those of controls by five and seven times, respectively. In gilts treated with 750 mg progesterone per day, plasma progesterone levels were 177.4 ± 22.1 ng/ml ($\text{x}\text{±}\text{SD}$) on day 3 and 186.4 ± 69.2 ng/ml on day 5 and resembled values found in superovulated pigs with more than 40 ovulations. Excessive plasma progesterone values of 1014.6 ± 840.4 ng/ml on day 3 and 473.2 ± 197.2 ng/ml on day 5 were found after treatment with 3000 mg of progesterone per day. Treatment with up to 750 mg of exogenous progesterone per day, did not affect embryonic development, but 3000 mg per day resulted in a significantly (P<0.001) higher percentage of retarded and degenerate embryos compared to controls (71.8% versus 3.2%).In addition, the amount and specificity of uptake of ³H-labelled progesterone and estradiol-17 beta by pig blastocysts recovered from superovulated gilts were investigated after 6 hrs in vitro culture. The uptake of ³H-progesterone was 131.9 ± 56.9 counts per million (cpm) per 10 blastocysts, corresponding to 1.1 fmoles progesterone. The uptake was non-specific for it was only slightly reduced in the presence of a 100-fold excess of unlabelled progesterone (20.1%) or estradiol-17 beta (27.0%). The uptake of ³H-estradiol-17 beta was 133.9 ± 74.12 cpm per 10 blastocysts, corresponding to 1.3 fmoles estradiol-17 beta. The uptake was significantly (P<0.01) reduced by 67.7% in the presence of a 100-fold excess of unlabelled estradiol-17 beta. Apparent specific binding was 0.87 fmoles estradiol-17 beta per 10 blastocysts or 72.5 fmoles estradiol-17 beta per mg protein. The uptake was only slightly reduced in the presence of a 100-fold excess of unlabelled progesterone (23.3%). This significant inhibition could be determined after 2 hrs in vitro culture. There was no competitive inhibition after 20 min. of culture.Uptake by unfertilized ova and degenerate embryos recovered on day 5 was significantly smaller (51.8 ± 10.3 cpm per 10 eggs; P<0.001) than by blastocysts recovered on the same day. No competitive inhibition could then be determined. In vivo, preimplantation pig embryos seem to be rather insensitive to high progesterone levels. Excessive amounts of progesterone probably can be metabolized to a great extent. Progesterone seems to be taken up rather non-specifically by the pig embryo. The uptake and binding of estradiol-17 beta seems to be more specific. Studies are in progress to investigate the physiological role of estradiol-17 beta uptake in early embryonic development.     

Distribution of estrogen receptor α and progesterone receptor B in the bovine oviduct during the follicular and luteal phases of the sexual cycle: an immunohistochemical and semi-quantitative study

Abstract

The aim of our study was to determine the distribution of estrogen receptor α (ERα) and progesterone receptor B (PR-B) in the bovine oviduct during the follicular and luteal phases. Bovine oviducts from 23 animals were obtained from a local slaughterhouse. Blood samples from these animals also were taken before death to measure estrogen and progesterone levels. The serum levels of estradiol-17β and progesterone changed during the estrous cycle. Tissue distribution of ERα and PR-B was examined using immunohistochemical techniques and the results showed that ERα and PR-B were stained in nuclei of cells and could be detected in all compartments along the entire oviduct during both the follicular and luteal phases. During the follicular phase, no significant differences were found between ERα and PR-B distribution (p < 0.05), while significant differences were found between ERα and PR-B during the luteal phase (p < 0.05). We results indicated that the frequency and intensity of ERα and PR-β immunoreactivity in the oviduct of bovines varied according to the oviductal cell types and the phases of the sexual cycle.     

Characterization of estrogen binding sites in the liver of the newt Pleurodeles waltl (Urodela:Amphibia): demonstration of a sex-linked heterogeneity

Saturation analysis over a wide range of [3H]estradiol-17 beta concentrations (1-40 nM) in cytosols prepared from liver of the newt Pleurodeles waltl of both sexes revealed a sex-linked heterogeneity of the estradiol-17 beta binding sites. In females, one type of binding site has been identified as a classical receptor. It exhibited a high affinity for estradiol-17 beta (Kd = 9 X 10(-9) M), had a high specificity for estrogenic compounds and was stabilized by monothioglycerol. In males, in addition to the receptor found in females, a second estrogen binding component was detected, not observed in female cytosols. It exhibited a Kd of 4.8 X 10(-8) M for estradiol 17 beta, higher capacity and displayed the same highly specific estrogen binding as does the estrogen receptor. It was affected by monothioglycerol and its binding was found to be significantly increased on cytosol dilution, as well as by estrogen-treatment.     

Expression of estrogen receptors in human corpus cavernosum and male urethra.

Estrogen, largely produced in testis and adrenal gland, may play important roles in male reproduction. Most of the effects of estrogens are mediated by binding of estrogen to one or both of the two estrogen receptor (ER) subtypes alpha and beta. Recently, they have been described in testis, prostate, and efferent ducts, mostly in rodents. The goal of this study was to prove the evidence of ERs in human corpus cavernosum and male urethra, exploring the protein expression of these receptors by immunohistochemistry. Corpus cavernosum and corpus spongiosum smooth muscle was immunoreactive for the androgen receptor (AR), ER alpha, and strongly for ER beta. Endothelial cells were negative for AR, sporadically positive for ER alpha, and positive for ER beta. Urethral epithelium showed strong nuclear expression of AR, predominantly in the basal cell layer, and nuclear expression of ER alpha in the intermediate cells. ER beta was highly expressed in almost all urethral nuclei and, much more weakly, in cytoplasm. Progesterone receptor (PGR) was negative in all cases and all tissues. These results represent the first report that ER alpha and particularly ER beta are regularly expressed in human penile tissue.     

Metabolism of 3H-estradiol-17 beta by cultures of isolated rat Sertoli cells and the effect of FSH: presence of 16 alpha-hydroxylase

The ability of Sertoli cells to metabolize 3H-estradiol-17 beta was investigated utilizing Sertoli cell cultures isolated from 18d rat testes. The Sertoli cells converted estradiol-17 beta to estriol as shown by recrystallization of estriol from samples containing cells and media but not from cell-free control media. The effect of FSH treatment on such metabolism was investigated and was shown to be similar to nontreated samples. This is the first demonstration that 16 alpha-hydroxylase is present in Sertoli cells and that this enzyme activity is not under the influence of FSH.     

Estradiol-17 beta inhibition of androgen uptake, metabolism and binding in epididymis of adult male rats in vivo: a comparison with cyproterone acetate

The effects of estradiol-17 beta on androgen uptake, metabolism and binding were studied in rat epididymis in vivo in comparison with cyproterone acetate. Steroids (250 ug/100 g body weight) were injected 5 min prior to 3H-testosterone in castrate rats. Estradiol-17 beta inhibited 3H-testosterone uptake into epididymal cytosol by 58% as compared to 38% by cyproterone acetate. 3H-Testosterone uptake into epididymal nuclei was inhibited 95% by estradiol-17 beta and 83% by cyproterone acetate. Total bound radioactivity in cytosol fractions was reduced to a greater extent by estradiol-17 beta than cyproterone acetate when either 3H-testosterone or 3H-dihydrotestosterone was injected. Binding of 3H-dihydrotestosterone to nuclear receptors was completely abolished by estradiol-17 beta; whereas approximately 20% binding remained in the nuclear extract after cyproterone acetate treatment. Metabolism of 3H-testosterone in vivo was also altered by estradiol-17 beta, resulting in diminished conversion to 3H-dihydrotestosterone. Cyproterone acetate, on the other hand, did not affect 3H-testosterone metabolism. Estradiol-17 beta and cyproterone acetate inhibited in vitro binding of 3H-dihydrotestosterone to the intracellular cytoplasmic receptor, but not the intraluminal androgen binding protein (ABP). These data suggest that estradiol-17 beta may have a more potent antiandrogenic effect on the epididymis than cyproterone acetate due to inhibition of 5 alpha reduction of testosterone as well as binding to the androgen receptor.     

Comparative observations on the morphology of the mammalian periovarial sac

The interspecific variation in the positional and mesenteric relationship of the mammalian oviduct to the ovary observed among 41 species is summarized by distinguishing eight morphological types of relationship. The recognition of types is based on wide species differences in: the position of the oviduct with reference to the mesosalpinxal fold and ovary; the extent to which oviducal mesenteries enclose the ovary in a periovarial sac; the degree of closure and method of formation of the peritoneal opening to the periovarial sac; and the morphology of the oviduct.     

Immunolocalization of estrogen receptor α in Neomysis japonica oocytes and follicle cells during ovarian development

Estrogen induces oocytes development and vitellogenesis in crustacean by interacting with estrogen receptor (ER) subtypes. In the present study, we detect for the first time the ERα in oocytes and follicle cells and hepatopancreas cells of mysis by immunohistochemistry using a specific ERα antibody. ERα was mainly localized in the nuclei of oocytes and follicle cells, while mainly detected in nuclei of oogonia (OG), previtellogenic oocyte (PR) and endogenous vitellogenic oocyte (EN) at previtellogenic and early vitellogenic stage (I-early III). Follicle cells in all stages of ovary (all vitellogenic stages) showed strong ERα positive reaction, and they were able to gradually move to oocytes during the development of oocytes. In addition, ERα was also localized in the nuclei and cytoplasm of four hepatopancreas cells (including E-, R-, F- and B-cell) in all ovary stages. These findings suggest, for the first time to our knowledge, that there could be a close link between oogenesis, follicle cells, hepatopancreas cells and endocrine regulation, and estrogens might be involved in the regulation of oocytes at early ovarian stage in mysis.     

Immunocytochemical localization of catechol-O-methyltransferase in the oviduct and in macrophages in corpora lutea of rat

Summary Catechol-O-methyltransferase (COMT) (EC 2.1.1.6) was localized in rat ovary, oviduct, and uterus using immunocytochemical methods. Immunoreactive deposits were found in the cytoplasm of macrophages in the ovary, epithelial cells of the oviduct, and glandular epithelial cells of the non-pregnant uterus. The pattern of localization observed in the extraneuronal elements suggests that enzyme may function in extraneuronal inactivation of catechols in the ovary, oviduct, and uterus.     

Estrogen receptor in the thymus of the castrated mice.

Sucrose density gradient ultracentrifugation and dextran-coated charcoal adsorption permitted us to characterize the estrogen-binding proteins in cytosols obtained from the thymus, spleen and mesenteric lymph node of the castrated male and female mice of C57BL strain. The thymic cytosol from both sexes incubated with 3H-estradiol-17 beta in the presence of excess unlabeled steroids showed a specific estrogenbinding 4 S protein with its binding capacity of 10(-14) moles/mg protein for males and 4 x 10(-15) moles/mg protein for females, respectively. The dissociation constant was of 4 x 10(-10) M for males and 3 x 10(-10) M for females, respectively. No specific binding was, however, found in the cytosols of the spleen and mesenteric lymph node. Steroid analysis by thin-layer chromatography of the thymic cytosols after incubation of them with 3H-estradiol-17 beta showed that a fair amount (around 60%) of radioactivity was from the undegradated radioactive steroid still bound to 4 S binder in both sexes. Enzyme study and heat experiment revealed that the estrogen specific 4 S binding component in the thymic cytosols bears at least protein in nature and is of heat-labile nature. These results strongly suggest that the thymus of the castrated mice contain a specific estrogen receptor, the nature of which is in part protein and heat-labile.     

Ultrastructure of Pharyngostomoides procyonis Harkema 1942 (Diplostomatidae). II. The female reproductive system

Several components of the female reproductive system of Pharyngostomoides procyonis, including the vitellaria and vitelline duct, ovary and oviduct, Laurer's canal, and Mehlis' gland and associated ducts, were observed with the electron microscope. Vitelline follicles contain cells in various stages of development. Mature vitelline cells contain membrane-delimited clusters of vitelline globules near the plasma membrane. Cilia are present in the vitelline duct. The ovary contains germ cells in various stages of maturation. Oogonia are found in the peripheral region. Mature oocytes contain numerous dense bodies near the plasmalemma. Also included in the cytoplasm of mature oocytes are "nucleolus-like bodies," myelin-like bodies, and mitochondria containing dense granules and few cristae. The epithelium of the oviduct is ciliated. Sperm are present in the oviduct and in Laurer's canal. Two types of secretory cells found in Mehlis' gland are described.