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1.
The fate of morphologically normal but chromosomally abnormal spermatozoa derived from mice with variable degrees and complexity of Robertsonian heterozygosity was studied at different sites along the male and female genital tract by Feulgen-DNA measurements. In addition, the percentage frequencies of morphologically abnormal spermatozoa in transit along the male and female genital tracts were studied. It was found that during transit from the epididymis to the vas deferens the distribution of the Feulgen-DNA contents of morphologically normal spermatozoa changed: Spermatozoa with chromatin with the extremely low or high Feulgen staining intensity disappeared. The percentages of morphologically abnormal sperm cells did not change at these levels. In the female genital tracts, the distribution of Feulgen-DNA content of morphologically normal spermatozoa did not show significant changes. This indicates that spermatozoa are able to reach the fallopian tube in spite of gross genome unbalance. There is evidence that unbalanced spermatozoa take part in the fertilization process, producing abnormal zygotes subject to postzygotic loss. Conversely morphologically abnormal spermatozoa were preferentially lost before they reached the fallopian tube, suggesting they had been eliminated prezygotically.  相似文献   

2.
Enkephalin-immunoreactive nerve fibers in the feline genito-urinary tract   总被引:1,自引:0,他引:1  
Summary Besides the classical neurotransmitters acetylcholine and norepinephrine the genito-urinary tract contains also neuropeptides. The distribution of substance P- and VIP-containing nerve fibers have earlier been described. Also enkephalin-immunoreactive nerve fibers occur in the male and female genito-urinary organs of the cat. The nerves are more numerous in male than in female genital tract. The prostatic gland and vas deferens receive the largest supply. In the female genital tract the enkephalin-immuno-reactive nerve fibers are regularly seen in the smooth muscle layer of the cervix. Of special interest is the rich occurrence of the enkephalin nerve fibers among the nerve cell bodies in the para-urethral and cervical ganglia supporting the view that enkephalin may play a neuromodulating role.  相似文献   

3.
The effect of male density on female reproductive fitness is still poorly understood in many insect species. Here we examined how male density influenced female mating behaviour, fecundity, longevity and damage to the genital tract in Sitophilus oryzae (L.) (Coleoptera: Curculionidae), an important pest of whole grains worldwide. We show that with increasing male density, (1) both male mate competition and female copulation duration significantly increased and (2) female fecundity, longevity and feeding time significantly decreased. Dissection indicates that the backward pointing spines on the reversed internal sac of male genitalia may grip and damage the female genital tracts. These results suggest that longer copulation and more frequent matings under higher male densities reduce the time for feeding and oviposition and increase the damage to female genital tracts. We conclude that the decreased female reproductive fitness under high male densities is most likely caused by a combination of the decreased feeding and oviposition time and increased damage to female genital tracts.  相似文献   

4.
Specimens from 4 chimpanzees were cultured for T-strain mycoplasma and Mycoplasma hominis. T-strain mycoplasmas were recovered from the genital tract and throat of a male and the genital tract of his female cagemate; neither had clinical evidence of infection. Two other male chimpanzees were culturally negative for T-strain mycoplasmas. M hominis was not isolated from any of the animals. The chimpanzee may serve as a suitable experimental model for studying the role of T-strain mycoplasmas in human urethritis and reproductive failure.  相似文献   

5.
Immunolocalization of glycodelin in the genital tract of rats   总被引:4,自引:0,他引:4  
Glycodelin, also known as placental protein 14 has been predominantly localized to organs of the human genital tract. Unfortunately the physiological role of glycodelin is largely unknown since it depends on limited availability of tissues. Therefore, a suitable animal model to study the role of glycodelin would be desirable. Previously, it was shown that glycodelin mRNA is expressed in the genital tract of male and female rats. In the present study, we demonstrate the expression of glycodelin protein in male and female rats by immunohistochemistry and Western blot analysis. For this purpose a polyclonal antibody was generated against glycodelin peptide. In female rats, glycodelin was found in the epithelial gland cells of the uterus, epithelial cells of the fallopian tube as well as in corpora lutea, interstitial and theca cells of the ovary. Glycodelin was distributed in all epithelial cells of the epididymis and the seminal vesicle. In the seminiferous epithelium, glycodelin was seen in all developmental stages of spermatogonia and spermatocytes and in Sertoli cells. Whereas in the rat male reproductive tract glycodelin expression is slightly different from human or primate tissues, in organs of the rat female genital tract glycodelin expression is similar to humans and primates.  相似文献   

6.
Men and women differ in their susceptibility to sexually transmittable infections (STIs) such as human immunodeficiency virus (HIV). However, a paucity of published information regarding the tissue structure of the human genital tract has limited our understanding of these gender differences. We collected cervical, vaginal, and penile tissues from human adult donors. Tissues were prepared with hematoxylin and eosin stains or immunofluorescence labeling of epithelial cell proteins and were analyzed for structural characteristics. Rhesus macaque genital tissues were evaluated to assess the use of this model for HIV/simian immunodeficiency virus transmission events. We found the stratified squamous epithelia of the male and female genital tract shared many similarities and important distinctions. Expression of E-cadherins, desmogleins 1/2, and involucrin was seen in all squamous epithelia, though expression patterns were heterogeneous. Filaggrin and a true cornified layer were markedly absent in female tissues but were clearly seen in all male epithelia. Desmogleins 1/2 were more consistent in the outermost strata of female squamous genital epithelia. Macaque tissues were similar to their respective human tissues. These initial observations highlight how male and female genital epithelia resemble and differ from one another. Further information regarding tissue structural characteristics will help to understand how STIs traverse these barriers to cause infection. This knowledge will be essential in future HIV pathogenesis, transmission, and prevention studies.  相似文献   

7.
目的:探究泌尿生殖道非淋茵性感染的病原学以及耐药性,指导临床合理用药。方法:对我院2006年3月.2011年12月确诊的2136例非淋菌性泌尿生殖道感染患者进行标本采集,对病原体及其耐药性进行检测分析。结果:淋茵感染泌尿生殖道病原茵主要为CT及支原体,男性患者CT感染率高于女性患者,女性患者支原体感染率高于男性患者,此外,念珠茵、滴虫及其他难以检出细菌亦属于致病病原茵的一种;在12种抗生素中,多西环素、米诺环素及交沙霉素敏感率较高,均〉80%,罗红霉素、红霉素及环丙沙星敏感度较低,均〈20%。结论:非淋茵感染泌尿生殖道病原菌主要为CT及支原体,男性患者CT感染率高于女性患者,女性患者支原体感染率高于男性患者,病原茵对多西环素、米诺环素及交沙霉素耐药性较低,但不同地域病原茵耐药性亦存在差异,应按照实际情况进行耐药性检测,指导临床合理用药。  相似文献   

8.
The morphology and histology of male and female reproductive systems were examined in Scoloplax distolothrix. Internal insemination was documented in this species by the presence of sperm within the ovaries. Mature males and females have elongated genital papillae, exhibiting a tubular shape in males and a plain heart‐shape with two median protuberances in females. The testes are two elongated structures that converge ventrally, under the intestine, towards the genital papilla. They are joined at the caudal end, forming an ovoid single chamber for sperm storage. Secretory regions were not observed. In the lumen of the testicular tubules, spermatozoa can be tightly packed along their lengths, but do not constitute a spermatozeugmata. The lumen of the sperm storage chamber and spermatic duct are filled with free spermatozoa without the accompanying secretions. The ovaries are bird‐wing shaped, saccular structures that converge ventrally under the intestine, towards the genital papilla. They are joined at the caudal end, forming a tubular chamber possibly destined for oocyte storage. An oviduct with an irregular outline connects the chamber to the tubular region of the genital papilla. No distinct sperm storage structure was found in the ovaries. The unique male and female genital papillae suggest that these structures are associated with the reproductive mode in scoloplacids, representing evidence for insemination. The occurrence of free spermatozoa, without the accompanying secretions and not arranged in a spermatozeugmata can be associated with the presence of a tubular male genital papilla for sperm transfer to the female genital tract. This reinforces the idea that sperm packets are not necessary for all inseminating species. The male reproductive system in scoloplacids is very different from that in auchenipterids, a second catfish family with insemination, which indicates that the occurrence of insemination is not connected to the internal morphology of reproductive organs. J. Morphol., 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

9.
10.
Male genitalia are among the most phenotypically diverse morphological traits, and sexual selection is widely accepted as being responsible for their evolutionary divergence. Studies of house mice suggest that the shape of the baculum (penis bone) affects male reproductive fitness and experimentally imposed postmating sexual selection has been shown to drive divergence in baculum shape across generations. Much less is known of the morphology of female genitalia and its coevolution with male genitalia. In light of this, we used a paternal half-sibling design to explore patterns of additive genetic variation and covariation underlying baculum shape and female vaginal tract size in house mice (Mus musculus domesticus). We applied a landmark-based morphometrics approach to measure baculum size and shape in males and the length of the vaginal tract and width of the cervix in females. Our results reveal significant additive genetic variation in house mouse baculum morphology and cervix width, as well as evidence for genetic covariation between male and female genital measures. Our data thereby provide novel insight into the potential for the coevolutionary divergence of male and female genital traits in a mammal.  相似文献   

11.
E Kubli  D Bopp 《Current biology : CB》2012,22(13):R520-R522
Drosophila male Sex Peptide elicits an amazing variety of postmating responses in mated females, some of which are transmitted via a receptor on specific neurons of the female genital tract. New work shows that neurons expressing the sex-determination gene doublesex (dsx) play a pivotal role in the female postmating switch.  相似文献   

12.
Adult chimpanzees (24 male, 76 female) with low and high rates of conception were examined for ureaplasmas, arginine-metabolizing mycoplasmas and chlamydiae. Ureaplasmas were isolated from the throat of only 1 male and 1 female animal, but from the urethra of 29% of the males and from the vagina of 95% of the females. Mycoplasmas were isolated from the throat more often than were ureaplasmas, but from the genital tract with about the same frequency as ureaplasmas. The numbers of organisms, of either type, isolated from the vagina were larger than the numbers isolated from the male urethra. Chlamydiae were not isolated from any animal. The occurrence of ureaplasmas and mycoplasmas and the numbers of these organisms isolated were similar in animals with low or high rates of conception. Furthermore, no association was noted between the organisms in the lower genital tract and the occurrence of abortion and/or stillbirth.  相似文献   

13.
The rapid evolutionary divergence of male genital structures under sexual selection is well documented. However, variation in female genital traits and the potential for sexual conflict to drive the coevolution between male and female traits has only recently received attention. In many lepidopterans, females possess genital teeth (collectively, signa). Comparative studies suggest these teeth, involved in the deflation of spermatophores, may have coevolved with male spermatophore thickness via sexually antagonistic coevolution in a contest over the rate of deflation of spermatophores within the reproductive tract. We tested the hypothesis that sexual conflict should generate coevolution between genital teeth and spermatophore morphology by examining these traits under experimental manipulation of sexual conflict intensity. Using micro‐CT scanning, we examined spermatophore and teeth morphology in populations of the Indian moth, Plodia interpunctella, which had been evolving for 110 generations under different adult sex‐ratio biases. We found divergence in female signa morphology in response to sexual conflict: females from female‐biased populations (reduced sexual conflict) developed wider signa. However, we found no evidence of coevolution between signa traits and spermatophore thickness as reported from comparative studies.  相似文献   

14.
Cytochemical quantitative measurements of isocitrate dehydrogenase (ICDH), malate dehydrogenase (MDH), cytochrome oxidase, lactate dehydrogenase (LDH), glucose 6-phosphate dehydrogenase (G6PDH) and glutamate dehydrogenase (GLDH) activities were made on rabbit spermatozoa collected from the testis, the different epididymal sites and the ductus deferens. These measurements were made on individual spermatozoa (at least 100 spermatozoa for each site under consideration) using a Vickers M 85 scanning microdensitometer.The activity patterns of the enzymes involved in the tricarboxylic acid cycle (ICDH, MDH) and in the respiratory chain (cytochrome oxidase) both showed a progressive decrease in the intramitochondrial oxidative metabolism from the testis to the ductus deferens. This was in contrast to LDH activity which represents the anaerobic glycolysis pathway rather than the activity of intramitochondrial LDH. The G6PDH activity could be related to those membrane modifications which the male gamete undergoes during its epididymal maturation. Potential GLDH activity was relatively intense in the spermatozoa from the testis and from the initial and distal segments of the genital tract, suggesting an intramitochondrial synthesis of enzymes such as cytochrome oxidase or ATPase.The quantitative variations of the enzymatic activities occurring during the transit of spermatozoa along the male genital tract suggested the existence of different specific interactions between the spermatozoon and the epididymal microenvironment.  相似文献   

15.
A study was undertaken to determine (1) the effects of endogenous Müllerian inhibiting substance (MIS) on the developing human fetal genital tract; (2) the time in fetal life when MIS is first capable of inhibiting the growth of the embryonic Müllerian ducts; and (3) the reversibility of the effects of MIS on the developing male Müllerian ducts. Human fetal reproductive tracts were transplanted and grown for sustained periods in vivo in athymic nude mice. The genital tracts from 12 male human fetuses, ages 51 to 68 days postovulation, were grafted without their associated gonads into castrated murine hosts and grown for 30 to 70 days. Controls consisted of genital tracts from 8 female human fetuses, ages day 53 to 70 that were grown under identical conditions. Male specimens grew to approximately one-half the size of female specimens and disclosed varying degrees of inhibition of the Müllerian duct system from absence of the Müllerian ducts in older specimens (after Day 63) to poorly segregated segments of stroma as the mildest defect (less than Day 61). It is concluded that (1) MIS secretion by the embryonic testes probably begins before Day 51 of gestation; (2) the effects of MIS are progressive during the so-called critical window; (3) the effects of MIS are permanent; and (4) the mesenchyme is an important target of MIS.  相似文献   

16.
It is now clear in many species that male and female genital evolution has been shaped by sexual selection. However, it has historically been difficult to confirm correlations between morphology and fitness, as genital traits are complex and manipulation tends to impair function significantly. In this study, we investigate the functional morphology of the elongate male intromittent organ (or processus) of the seed bug Lygaeus simulans, in two ways. We first use micro-computed tomography (micro-CT) and flash-freezing to reconstruct in high resolution the interaction between the male intromittent organ and the female internal reproductive anatomy during mating. We successfully trace the path of the male processus inside the female reproductive tract. We then confirm that male processus length influences sperm transfer by experimental ablation and show that males with shortened processi have significantly reduced post-copulatory reproductive success. Importantly, male insemination function is not affected by this manipulation per se. We thus present rare, direct experimental evidence that an internal genital trait functions to increase reproductive success and show that, with appropriate staining, micro-CT is an excellent tool for investigating the functional morphology of insect genitalia during copulation.  相似文献   

17.
Despite the key functions of the genitalia in sexual interactions and fertilization, the role of sexual selection and conflict in shaping genital traits remains poorly understood. Seed beetle (Callosobruchus maculatus) males possess spines on the intromittent organ, and females possess a thickened reproductive tract wall that also bears spines. We investigated the role of sexual selection and conflict by imposing monogamous mating on eight replicate populations of this naturally polygamous insect, while maintaining eight other populations under polygamy. To establish whether responses to mating system manipulation were robust to ecological context, we simultaneously manipulated life-history selection (early/late reproduction). Over 18-21 generations, male genital spines evolved relatively reduced length in large males (i.e., shallower static allometry) in monogamous populations. Two nonintromittent male genital appendages also evolved in response to the interaction of mating system and ecology. In contrast, no detectable evolution occurred in female genitalia, consistent with the expectation of a delayed response in defensive traits. Our results support a sexually antagonistic role for the male genital spines, and demonstrate the evolution of static allometry in response to variation in sexual selection opportunity. We argue that further advances in the study of genital coevolution will require a much more detailed understanding of the functions of male and female genital traits.  相似文献   

18.
Summary The study of LRH reactive neurons of the medial basal hypothalamic group was made with rabbit antisera to unconjugated synthetic LRH, in normally cycling female squirrel monkeys.The specifically immunoreactive material present along the hypothalamo-infundibular LRH tract shows significant modifications that are particularly distinct in the lateral, posterior and anterior labia of median eminence, with a maximum concentration during the early and middle follicular phases, a sudden fall to a minimum concentration during the late follicular and ovulatory phases and with a progressive increase during the luteal and early follicular phases.Serum FSH and LH levels show a progressive decrease from the luteal phase to the late follicular phase, with differential modifications suggesting that a double regulation might take place in cycling squirrel monkeys.A parallel is suggested between the specifically reactive material along the hypothalamo-infundibular tract, serum gonadotropin levels and variations in the medial basal hypothalamic and infundibular LRH concentrations during the estrous cycle in the squirrel monkey.This work was supported by the D.G.R.S.T. (contrat 76-7-1536) and U.E.R. 3 (Faculty of Medicine). We acknowledge the help of A. Pillez (C.N.R.S.) for sectioning and staining the genital tracts  相似文献   

19.
Sperm competition is a pervasive force. One adaptation is the male ability to displace the rivals' sperm that females have stored from previous copulations. In the damselfly, Calopteryx haemorrhoidalis asturica , males with wider aedeagi displace more spermathecal sperm. The present study documents that the same mechanism operates in another damselfly, Hetaerina americana . However, this genital width in both species decreases along the season, but late-emerging females have more sperm displaced than early-emerging females. Because territorial males mated more and were larger in body and genital size than nonterritorial males, late-season females mated with considerably larger males with respect to female size and this produced higher sperm displacement. Assuming female benefits from storing sperm but that such benefit does not prevail if males displace sperm, it is predicted that, along the season, females will mate less and male harassment (in terms of male mating attempts and oviposition duration) will increase. These predictions were corroborated. In H. americana , it was also tested whether spermathecal sperm became less viable along the season. The results obtained did not corroborate this. This is the first evidence indicating that season affects sperm displacement ability and female mating frequency due to changes in male body and genital size.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 815–829.  相似文献   

20.
The first phase of spermiogenesis in argasid and ixodid ticks is described. The inner core of the spermatid passes through the outer sheath so that speriogenesis is permitted to follow its course. The outer sheath is not ruptured in the process, but a well-defined operculum opens to let the inner core through. The opening of the operculum is a clear-cut indication of the beginning of spermiogenesis. In the examined species speriogenesis begins in Argasidae when the male transfers the spermatophore to the female genital opening, whereas in Ixodidae it starts only after the endospermatophore has reached the female genital tract.  相似文献   

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