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1.
嘉庚蛸雌性生殖系统组织学观察   总被引:2,自引:0,他引:2  
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...  相似文献   

2.
The present study aimed at assessing the annual reproductive cycle of female Arabian carpetshark, Chiloscyllium arabicum from the Persian Gulf by a macroscopic and microscopic evaluation of the reproductive tract. The annual cycle of gonadal steroids [17β-estradiol (E2), progesterone (P4) and testosterone (T)] was also assessed in this shark. In total, 130 female C. arabicum were collected from the Bahrakan Creek (located northwest of the Persian Gulf) between January 2018 and March 2019. Females were oviparous with an external-type ovary and only one functional ovary. Five sexual maturity stages were recognized based on macroscopic and microscopic evaluation: Immature I (August–October), Immature II (November–January), Mature (February–March), Pregnant (April–May) and Spent (June–July). The structural changes in the oviducts, oviducal glands and uterus throughout the annual reproductive cycle were consistent with their roles in the egg movement, the egg capsule production and sperm storage. The plasma levels of the gonadal steroids were associated with morphological changes in the reproductive tract. E2 showed two detectable peaks during March (close to ovulation) and June (just before mating). P4 and T displayed a peak just before ovulation.  相似文献   

3.
4.
Laparoscopic observations of morphological changes of the ovary during the ovarian cycle in conjunction with radioimmunoassay of serum progesterone and estradiol-17β was investigated as a method of monitoring the ovarian cycle in the common marmoset. In the common marmoset, plural follicles first appeared in each ovary five days prior to ovulation. At three to four days prior to ovulation one or two follicles developed into translucent blisters on the surface of the ovary. As the follicles filled with follicular fluid, they became larger and clearer until one to two days prior to ovulation, at which time they formed well defined, transparent bubbles protruding from the surface of the ovary. After ovulation, the ovulation point could be detected at the center of the follicle, sometimes surrounded by a corpus of engorged blood vessels. Ovulations of the plural follicles were not simultaneous, and due to the time lag ovulations took at least 12 to 20 hrs in four out of seven animals examined. After two to five days of ovulation the corpus hemorragicum, a bright red protrusion made of tissue and blood disrupted by ovulation, was found. Subsequently, the color of the formatted corpus luteum changed from dark-red to yellow then to yellow white. While the corpus luteum remained reddish in color serum progesterone was maintained at as high levels as in the luteal phase. There was no mature follicle or corpus luteum in subordinate female ovaries.  相似文献   

5.
Females of the squirrelfish family (Holocentridae) accumulate higher levels of hepatic zinc than any other studied animal. This accumulation is accompanied by high expression of the zinc-binding protein, metallothionein (MT), and is strongly correlated to the onset of sexual maturity. In an attempt to further characterize the timeframe of this accumulation, and to possibly discern any potential mediators, we examined the physiology and endocrinology of the yearly reproductive cycle of mature female squirrelfish. There are two separate reproductive events during the year in December-January and again in March-April, as evidenced by peaks in ovarian growth, VTG production, steroid levels, zinc accumulation and redistribution. Increased hepatic zinc seems to be preceded by a necessary increase in MT, but this was not clearly correlated to plasma 17beta-estradiol, testosterone, or progesterone levels. The plasma zinc protein vitellogenin (VTG) is one, but probably not the predominant, vehicle for the transport of hepatic zinc to the ovary.  相似文献   

6.
交配是蜱类繁殖过程的关键环节,诱发雌蜱发生一系列的生理变化,并最终产卵。蜱雄性附腺分泌物在交配过程中发挥着重要作用,具有保护、活化精子,促进受精、卵巢发育和卵黄发生的功能,并对雌蜱的生殖生理行为等产生影响,如诱导雌蜱快速吸血和加速产卵。本文在简要分析蜱雄性附腺结构和分泌物生化特性基础上,系统阐述了蜱雄性附腺分泌物中各种功能因子的研究现状,着重论述其在精子获能、诱导雌蜱吸血、促进雌蜱卵巢发育和卵黄发生等方面的进展,并对未来研究提出了展望,以期为此领域的研究拓展思路。  相似文献   

7.
Vertebrate-type steroids, such as progesterone, have been identified in crustaceans. The physiological activity of progesterone during vitellogenesis is still not well understood. In this study, progesterone levels in the female mud crab, Scylla paramamosain, were determined by enzyme-linked immunosorbent assay. Peak levels of progesterone were detected during the previtellogenic stage in the hemolymph, ovary, and hepatopancreas, whereas the progesterone level decreased significantly in vitellogenic stage I. During vitellogenic stage II, progesterone levels rose again in the hemolymph and ovary, but continued to decrease in the hepatopancreas. By using western blotting, progesterone receptor (PR), with an apparent molecular weight of 70 kDa, was identified in the ovary during both vitellogenic stages I and II. By means of immunohistochemistry, PR was detected mainly in the follicle cells during vitellogenic stage I and in the nuclei of oocytes in vitellogenic stage II. Our results strongly suggest that progesterone promotes vitellogenesis in the mud crab, S. paramamosain via a classical genomic mechanism.  相似文献   

8.
Uterine cervical mucus contains an immunoglobulin binding factor (IgBF). It may play a role in preventing antibody production against sperm in the female reproductive tract. To elucidate the mechanism involved in the production of activated IgBF, we determined the effects of hormones on the expression of mRNAs of IgBF and of protein disulfide isomerase (PDI), activating enzyme, in uterine cervix by quantitative RT-PCR. The uterine cervices of female rats were excised at preovulatory, ovulatory, and postovulatory phases. The human uterine cervical adenocarcinoma cells (TCO-2) were cultured for 24 h in serum-free medium containing 17beta-estradiol or progesterone. Expression of IgBF and PDI mRNAs was significantly highest during the ovulatory phase. 17beta-estradiol stimulated the expression of both mRNAs in TCO-2; whereas progesterone was ineffective. In conclusion, estrogen regulates the production of IgBF by the endocervix and PDI in vivo, thereby increasing the level of activated IgBF in the female reproductive tract during the ovulatory phase, allowing sperm to enter the uterine cavity.  相似文献   

9.
Plasma concentration of progesterone and 17beta-estradiol of black-rumped agouti (Dasyprocta prymnolopha) during the estrous cycle. The agouti is a game animal that have been raised in captivity for conservation and sustainability purposes. However, the management of wild animals in an intensive breeding system requires an assertive knowledge of its reproductive parameters, one of the most important features for production improvement. Besides, little information is available regarding changes in reproductive hormone profiles in agouti. The objective of this study was to evaluate the hormonal profile of progesterone and 17beta-estradiol during the estrous cycle of the agouti (Dasyprocta prymnolopha). The hormones were analyzed by radioimmunoassay. Blood samples were collected without sedation twice a week. The concentrations of progesterone were as follows: proestrus 0.78 +/- 0.39 ng/ml, estrus 2.83 +/- 2.34 ng/ml, metestrus 1.49 +/- 1.24 ng/ml, diestrus 3.71 +/- 1.48 ng/ml. In the estrous phase, an increase in the progesterone level was observed during a period of 24h. The average 17 beta-estradiol levels were as follows: proestrus 2 030.98 +/- 961.00 pg/ml, estrus 1 910.56 +/- 650.54 pg/ml, metestrus 1 724.83 +/- 767.28 pg/ml, diestrus 1 939.94 +/- 725.29 pg/ml. The current results suggest that the progesterone plasma concentration during the estrous cycle in the agouti has a similar increasing, stabilizing and decreasing pattern, as in domestic mammals. Agoutis have two phases of follicular development, as two periods of 17beta-estradiol peaks were observed, the first one in the metestrus and the second during the proestrus. Spontaneous ovulation seems to occur after the progesterone peak, possibly indicating that this hormone is associated with the ovulatory process. A more detailed investigation is needed for better understanding of how progesterone influences ovulation. Studies on the involvement of progesterone in follicular rupture can be carried out, using steroid biosynthesis inhibitors and observing the effect of this hormone on ovarian activity of proteolytic enzymes in the follicular wall.  相似文献   

10.
This study examined the endocrine and reproductive correlates of reproduction in 636 female and 468 male draughtboard sharks (Cephaloscyllium laticeps) captured from southeastern Australia. Females were oviparous and displayed a single external-type ovary with a maximum follicle diameter of 35 mm. Vitellogenesis commenced at a follicle diameter of 10 mm. Females showed a constant overlap between follicular recruitment, ovarian growth, and egg laying. The male reproductive tract consisted of paired testes with spermatocysts undergoing diametric development. Plasma levels of the presumptive gonadal steroids, testosterone (T), 17beta-estradiol (E2), progesterone (P4), and 11-ketotestosterone (11-KT; males only) were correlated with morphological developmental stages of the gonads. In females, E2 increased as the follicle developed before declining as the follicle reached maturity. T remained low during the first stages of ovarian growth and increased as the follicle reached maturity. P4 showed a peak just before ovulation. In males, T was the only hormone that varied with maturity, increasing in adults; E2 and P4 were present at low plasma concentrations in males and did not change with stage of gonadal development. 11-KT was undetectable at all times. Endocrine changes in draughtboard sharks were consistent with hormonal correlates reported for other species and suggest roles for E2( in females) and T (in both sexes) in gametogenesis and P4 in maturational events in females.  相似文献   

11.
The reproductive cycle of the Australian sharpnose shark, Rhizoprionodon taylori, includes a temporary suspension of development at the commencement of embryogenesis termed embryonic diapause. This study investigated levels of 17β-estradiol (E2), testosterone (T) and progesterone (P4) in plasma samples of mature wild female R. taylori captured throughout the reproductive cycle and correlated them with internal morphological changes. Levels of T were elevated through most of the embryonic diapause period, suggesting a role of this hormone in the maintenance of this condition. Increasing plasma T concentrations from late diapause to early active development were associated with a possible role of androgens in the termination of embryonic diapause. As in other elasmobranchs, a concomitant increase of E2 with ovarian follicle size indicated a direct role of this hormone in regulating vitellogenesis, while a peak in P4 suggested this hormone is associated with preovulation and ovulation. Additionally, significant correlations between photoperiod or water temperature and maximum follicular diameter and hepatosomatic index suggest that these abiotic factors may also play a role triggering and regulating the synchrony and timing of reproductive events.  相似文献   

12.
To obtain basic information on the properties of the intraovarian cavity leucocytes (IOCLs) of the viviparous teleost, Neoditrema ransonneti, morphological characteristics and numerical changes of IOCLs during the reproductive cycle were investigated. In the ovaries of newborn females, leucocytes exuded into the lumen were observed first in November, prior to insemination of semen. These cells were primarily macrophages, neutrophils and lymphocytes. Among them, macrophages were invariably the largest population throughout the reproductive cycle. They began to phagocytize spermatozoa in December, when spermatozoa were first detected in the ovary. The number of IOCLs gradually increased from November in the newborn female. However, this increase is not ascribed to the effect of copulation or the presence of semen, because the number of leucocytes also increased in non-mating fish. While developing embryos were discharged into the ovarian lumen at the latest in January, a number of spermatozoa and spermatozoa-phagocytizing macrophages were seen until March. Even after the extinction of sperm cells, numerous IOCLs remained in the lumen and coexisted with fetuses until their parturition. These results suggest that IOCLs play roles in successful pregnancy, besides elimination of remaining spermatozoa.  相似文献   

13.
Summary The ovaries of the starfish Asterias rubens were studied histologically and ultrastructurally. The reproductive system in female specimens consists of ten separate ovaries, two in each ray. Each ovary is made up of a rachis with lateral primary and secondary folds: the acini maiores and acini minores. The ovarian wall is composed of an outer and an inner part, separated by the genital coelomic sinus. The ovarian lumen contains oocytes in various phases of oogenesis, follicle cells, nurse cells, phagocytosing cells and steroid-synthesizing cells.Oogenesis is divided into four phases: (i) multiplication phase of oogonia, (ii) initial growth phase of oocytes I, (iii) growth phase proper of oocytes I, and (iv) post-growth phase of oocytes I. The granular endoplasmic reticulum and the Golgi complex of the oocytes appear to be involved in yolk formation, while the haemal system, haemal fluid and nurse cells may also be important for vitellogenesis. The haemal system is discussed as most likely being involved in synchronizing the development of the ovaries during the annual reproductive cycle and in inducing, stimulating and regulating the function of the ovaries.Steroid-synthesizing cells are present during vitellogenesis; a correlation between the presence of these cells and vitellogenesis is discussed.  相似文献   

14.
The sites of action and the physiological role of estrogens and progesterone in the ovary are poorly understood in Reptiles. We have undertaken a systematic study of the immunoexpression of classical oestrogen receptor (ER or ERalpha) and progesterone receptor (PR) in the female lizard during the reproductive cycle. During vitellogenesis, ER was not expressed in vitellogenic follicles whereas PR was weakly detected in the nucleus of some follicular cells and well expressed in the internal theca cells. The follicular and theca cells were immunopositive for ER in the previtellogenic follicles, the signal in both was cytosolic. PR was strongly expressed in the follicular cells, the signal was localised in the nucleus. In the post-reproductive period, ER was detected in the previtellogenic follicles in the same manner as in the breeding period. The staining for PR was expressed in both the nucleus and cytoplasm of follicular cells and theca cells. In the sexual rest, the previtellogenic follicles were all negative for ER and PR immunoexpression. These findings suggest that the main action of estrogens in the ovary is not mediated by ER. The expression of cytosolic PR only in the post-reproduction period, at the same time at the progesterone synthesis, supports the hypothesis which stipulates an exclusive nuclear localization in the absence of progesterone.  相似文献   

15.
【目的】探明田间草地贪夜蛾Spodoptera frugiperda卵巢的发育状态及其变化,为草地贪夜蛾种群的发生和迁飞动态提供精准监测依据。【方法】采用雌性生殖系统解剖法,比较不同日龄和地区的田间草地贪夜蛾雌蛾卵巢的形态差异,分析卵巢成熟状态与雌蛾交配的关系。【结果】草地贪夜蛾雌蛾生殖系统包含卵巢、输卵管、交配囊、导精管、受精囊、附腺和产卵器。根据形态特征可以将田间草地贪夜蛾卵细胞分为卵黄发生前期、卵黄期和成熟期3个时期。田间雌蛾1日龄卵巢中发育最快的卵仅处于卵黄期中期,卵巢管柄为空;3日龄卵巢出现分化,一部分卵巢仍然和1日龄相似,另一部分卵巢中存在成熟卵;这种卵巢发育分化到羽化后11 d时仍然存在。云南江城、弥勒,广西田阳以及浙江瑞安和镇海等地的田间雌蛾,到死亡时分别有61.5%, 51.7%, 41.7%, 42.1%和35.5%卵巢发育不成熟。室内饲养第1代雌蛾中,有39.6%的个体到死亡时卵巢未发育成熟,和田间雌蛾比例相似。交配雌蛾卵巢可以是发育成熟和未成熟的,但是未成熟卵巢的比例仅为18.0%±5.0%。【结论】结果提示同一代次的田间草地贪夜蛾可能同时存在迁飞和非迁飞个体,其比例随地理位置和季节发生变化。本研究的结果在一定程度上解释了单纯依据化学农药难以防治草地贪夜蛾的原因,也为田间草地贪夜蛾的迁飞监测和绿色防控提供了一定依据。  相似文献   

16.
Changes of growth hormone receptivity in the ovary during the reproductive cycle were studied in rainbow trout (Oncorhynchus mykiss). A method for characterizing growth hormone receptors in crude ovary homogenate was required for this. Binding of radiolabelled recombinant rainbow trout growth hormone (125I-labelled rtGH) to crude ovary preparation was dependent on ovarian tissue concentration. The sites were specific to growth hormone, with no affinity for prolactins and gonadotrophins. Similar high affinities for 125I-labelled rtGH were obtained with crude ovary (4.2 x 10(9) +/- 0.3 mol l-1) and crude liver preparations (4.9 x 10(9) +/- 0.1 mol l-1) at all stages of ovogenesis, and with ovarian membrane preparations (8.2 x 10(9) mol l-1) tested at the beginning of vitellogenesis. Ovarian growth hormone receptor concentration was highest during the early phases of follicular development (endogenous vitellogenesis: 315-310 fmol g-1 ovary) and decreased regularly during oocyte and follicular growth (exogenous vitellogenesis) to reach a minimal value at oocyte maturation (42 fmol g-1 ovary). In postovulated fish, binding was at a similar level (297 fmol g-1 ovary) to that found in endogenous vitellogenesis. Conversely, the absolute binding capacity of the whole ovary was low from immaturity to early exogenous vitellogenesis (0.1-0.6 pmol per pair of gonads), increased slowly during vitellogenesis and more markedly during rapid oocyte growth and at the time of final maturation (10.8 pmol per pair of gonads). In postovulated fish, the absolute binding capacity decreased partially (4.4 pmol per pair of gonads). Mean hepatic growth hormone receptor concentration did not vary with the reproductive stage for most of the cycle (3.0-4.5 pmol g-1 liver) except in endogenous vitellogenesis where significantly higher concentrations were observed (6.7 pmol g-1 liver). Individual ovarian growth hormone receptor concentrations were correlated with hepatic growth hormone receptor concentrations, indicating that they are regulated in a similar way. We conclude that growth hormone receptors are present in the ovary during the entire ovarian cycle in rainbow trout, probably mainly in somatic cells as indicated by the same concentration of binding sites in immature and in postovulated fish. Growth hormone is potentially important during oocyte recruitment in vitellogenesis and initiation of growth and during final follicular maturation.  相似文献   

17.
Plasma patterns of prostaglandin F2 alpha (PGF2 alpha) and sex hormones (progesterone, androgens and 17 beta-estradiol) have been studied in the female crested newt, Triturus carnifex (Laur.), during the annual sexual cycle. The effects of exogenous PGF2 alpha on sex hormones were determined. In addition, the effects of one week's captivity on plasma PGF2 alpha and sex hormones were reported. PGF2 alpha plasma level peaked in April, was low in summer, and progressively increased during the autumn to peak again in December. The April PGF2 alpha coincided with a 17 beta-estradiol rise, and with a progesterone drop. The autumn PGF2 alpha increase was coupled to a 17 beta-estradiol rise, and therefore it has been tentatively related to ovary and oviduct development. In newts collected in April, moreover, a PGF2 alpha-dependent 17 beta-estradiol synthesis could occur, since PGF2 alpha injection induced a significant 17 beta-estradiol plasma increase. These findings led us to suppose that PGF2 alpha intervenes in spring breeding season termination through the induction of a 17 beta-estradiol synthesis as in other amphibian species. PGF2 alpha injection caused a progesterone decrease, probably by inducing corpora lutea lysis. The patterns of plasma sex hormones were consistent with the results reported for the same newt species.  相似文献   

18.
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.  相似文献   

19.
The ultrastructure of the ovary of Paragonimus ohirai was investigated in different developmental stages of experimental infection in rats, from the metacercarial stage to the adult stage. The female reproductive cells were observed in order to understand the development of the ovary. During its development in the definitive host, the ovarian primordium and the ovary increased in size and cell number and underwent morphological changes. The blind end of the female genitalia was an undifferentiated primordium at the metacercarial stage, but became the bud of an ovary on day 3. Germ cells and supporting cells were observed on day 5. Oogonia were identified in the 15-day-old ovary, followed by the appearance of young oocytes at 17 days. Large oocytes were found on day 19, but the 21-day-old ovary contained degenerated oocytes. Mature ovaries were observed in the 26-day-old worms and egg formation was seen to arise on day 28. The development of the ovary and female reproductive cells was discussed in relation to the physiology of P. ohirai.  相似文献   

20.
To provide updated information on life history for improved fishery management, the reproductive cycle of the finetooth shark Carcharhinus isodon from Northwest Atlantic (NWA) populations was investigated by examining temporal changes in morphology and histology of reproductive organs. Changes in plasma concentrations of gonadal sex hormones in relation to reproductive stage were also examined. Increases in testis width, epididymis head width, plasma testosterone concentrations and occurrence of mature spermatozoa were observed in male sharks between December and April, suggesting a seasonal pattern in reproduction that culminates with copulatory activity in May. Increases in maximum follicular diameter, oviducal gland width, plasma 17β-estradiol concentrations and occurrence of vitellogenic follicles were observed in non-pregnant female sharks during the same time period along with the occurrence of newly pregnant females in May, demonstrating strong synchronicity between male and female reproductive cycles. Pregnant females bearing full-term embryos were also observed in May, indicating that parturition occurs between mid-May and early June and gestation requires 12 months. Only transient temporal changes in follicle size and oviducal gland width were observed in pregnant females, indicating that reproductive periodicity is biennial; nonetheless, a single female exhibiting signs of concurrent vitellogenesis and pregnancy was observed. Mean brood size ± S.D. was 3.9 ± 0.9 offspring/female. Fecundity was not significantly correlated with female size, in part due to an unexpectedly high rate of early embryo mortality, which occurred in 11% of pregnant females, and was more common in larger individuals. Changes in ovarian activity during mid-pregnancy were observed, suggesting possible roles for the ovary in regulating some aspects of early to mid-gestation. This study confirms that earlier characterizations of the reproductive cycle and fecundity in NWA finetooth sharks remain valid for use in fishery management. This study also highlights unusual features of finetooth shark pregnancy (e.g., early embryo death, mid-pregnancy changes in ovarian function) that may have broader relevance to understanding elasmobranch reproduction.  相似文献   

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