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1.
A case of disrupted embryonic development of the genital tract in a newborn Holstein calf is described. The physical examination of the calf evidenced several abnormalities, like atresia ani, rudimentary external genitalia and caudal vertebral agenesis. On necropsy, the excised genitalia consisted of bilateral streak gonads, apparently normal uterine tubes, a fluid-filled uterus, a long vagina and a very narrow clitoris-like structure covered with a discrete skin-fold. The urinary tract seemed normal and the urethra's opening was at the vestibule-vaginal junction. A cytogenetic analysis was requested. Karyotype revealed the existence of Y chromosome material in the two X chromosomes. However, the search for the sex-determining region Y (SRY) showed that this was an apparently absent gene. The histological examination of the gonads revealed the existence of ovarian dysplasia. Uterine sections evidenced the absence of the uterine epithelium, with only sporadic caruncles. Under microscopic examination, the uterine tubes and vagina structure was normal. The external genitalia sections revealed the existence of a skin-fold covering an erectile structure surrounding the urethra, a structure more similar to a penis than to a clitoris. This is an unusual situation of gonadal dysplasia combined with genital tract anomalies in cattle, probably associated to a genetic defect.  相似文献   

2.
Administration of 50 micrograms of testosterone propionate to newborn female rats on the 5th day of life provoked a reliable increase in noradrenaline and dopamine concentrations in the hypothalamus of 10-day-old rats. Neonatal administration of aromatase inhibitors on the 5th and 7th days of life prevented testosterone-induced increase in catecholamine concentrations. The data obtained prove the integration of the processes of testosterone aromatization and catecholamine accumulation in androgen-dependent brain differentiation.  相似文献   

3.
Male and female offspring of rats given antiandrogens, the steroidal BOMT or the non steroids DIMP or Sch 13521, daily during the last third of pregnancy were studied. Detailed examinations were made of the genital tract of male, and of the nipples of male and female offspring. A) Male offspring. 1) Genital tract of newborn and 31-91 day old males : Modifications of the development of accessory sexual tissues were found in all treatment groups. As indicated by the severity of deviations from normal (morphology and weight of sex accessories), the antiandrogenic effect of the preparations, in the doses given to the mother rats, increased from BOMT (50 or 75 mg/day) via Sch 13521 (30 mg/day) and DIMP (50 or 60 mg/day) to Sch 13521 (60 mg/day). 2) Nipples of 10-60 day old males : Whole mount preparations were made unilaterally of the row of 6 mammary glands with nipples. The number of intact and abnormal nipples, respectively, was recorded. The relation between intact and abnormal nipples served as indicator of the efficiency of the antiandrogenic substances studied. The result showed that the antiandrogenic effect increased from BOMT to Sch 13521, 60 mg, in the same order as that arrived at from studies of the genital tract. The combined results obtained from the male offspring indicated that the tissues of the genital region, the growth and differentiation of which was most readily impaired by antiandrogens, were the same as those known from other work to be stimulated most easily in female rat fetuses by testosterone. B) Female offspring. Nipples of 31-60 day old females were judged from whole mount preparations and recorded as in the males. The nipples of adult virginal females were examined macroscopically. The same procedure was applied to lactating females, but the results were controlled in consecutive lactational periods and at autopsy. The 3 groups of females showed uniformly that 1) offspring of rats given BOMT during pregnancy had many (about 50 per cent) malformed nipples and 2) the treatment of mother rats with DIMP or Sch 13521 did not influence the development of nipples in female offspring. The result was assumed to be due to an androgenic effect of the steroidal antiandrogen, BOMT, on the nipple anlage.  相似文献   

4.
The ability of clomiphene and its isomers to cause estrogenic responses during the neonatal period in the rat was examined. Rats were injected s.c. with clomiphene (CL), zuclomiphene (ZUC) or enclomiphene (ENC) on days 1,3, and 5 of life and the stimulation of the reproductive tract and estrogen receptor binding was observed. Uterine weight and DNA content were increased significantly by day 7 in animals treated with clomiphene or zuclomiphene. Uterine epithelial hypertrophy was present in all groups by day 10 and hyperplasia was present in the animals treated with ZUC and CL. The time of vaginal opening was greatly accelerated in all drug treated groups with the earliest day of opening occurring on day 7. Ovarian hemorrhage and blood in the periovarian sac occurred between days 12-14 and continued to be present through day 25. Drug treatment caused the estrogen receptor to accumulate in the nuclear fraction of the uterus and to be depleted from the cytosol fraction. We conclude that clomiphene administered to neonatal rats causes estrogenic stimulation of the reproductive tract in a fashion similar to other estrogens. This stimulation may account for the reproductive tract abnormalities which develop in rats treated with those drugs during the neonatal period.  相似文献   

5.
Adrenal and ovarian relative influence over rat uterus estrogenic receptor, both cytosolic (RcE) and nuclear (RnE) ontogenesis, has been studied. Ovarian influence has been studied by practising bilateral ovariectomy the first day of life and examining estrogenic receptor content evolution from, birth to puberty in these ovariectomized animals (OVX1) by comparison with the normal ones. This influence seems to be of scarce importance until the 20th day of life, since estrogenic receptors content is practically coincident in the OVX1 animals and in the control ones. From the 20th day, ovarian secretion influence increases and estrogenic receptor evolution starts evolving in a different way in the two types of animals. Adrenal influence has been studied by practising bilateral adrenalectomy on the 10th or 30th day of life to OVX1 animals or else OVX and ADX on the 10th or 30th day. Adrenal influence in the upkeep of high estrogen receptor levels on the 10th day, seems to be important, since in the absence of these glands it decreases in a considerable way. The situation is different on the 30th day. At this age ovarian secretion seems to be the most important in maintaining estrogen receptor levels, while adrenal secretion effects tend to inhibit them, especially RnE.  相似文献   

6.
We show the existence of functional vasoactive intestinal peptide (VIP) receptors in normal human female genital tract (endometrium, myometrium, ovary and Fallopian tube) as well as in leiomyoma (a frequent uterine pathology). The correlation between VIP binding and stimulation of adenylyl cyclase activity for all studied tissues was linear (r = 0.86) suggesting the expression of VIP receptors throughout the human female genital tract. Immunodetection of VIP receptor subtypes gave different molecular weights for VPAC(1) (47 kDa primarily) and VPAC(2) (65 kDa), which may be due to different glycosylation extents. In conclusion, this study demonstrates the expression of both subtypes of VIP receptors and their functionality in human female genital tract, suggesting that this neuropeptide could play an important physiological and pathophysiological role at this level.  相似文献   

7.
H J Dean  J S Winter 《Steroids》1984,43(1):13-24
The suggestion has been made that prenatal exposure to synthetic progestogens contributes to an increased incidence of hypospadias. One potential mechanism for such an effect might be inhibition of 5 alpha-reductase, a key enzyme in normal male sexual differentiation. We have examined the effect of progesterone and of five synthetic progestogens upon 5 alpha-reductase activity in fibroblast monolayers from 12 genital skin cell lines obtained from normal newborn infants, boys with phimosis and hypospadias and a normal adult male. Basal enzyme activities ranged from 0.8-12.1 pmoles 5 alpha-reduced product/micrograms DNA/hour. Progesterone and norethindrone inhibited 5 alpha-reductase activity in a dose dependent manner to a maximum of 95% and 50% of basal levels respectively at 10(-5) M. Similar concentrations (10(-5) M) of norethynodrel, ethisterone, dl-norgestrel and d-norgestrel had little or no effect. Studies of cell viability showed that the effects of progesterone and norethindrone were specific for 5 alpha-reductase and not non-specific toxic effects.  相似文献   

8.
A S Loktionov 《Ontogenez》1980,11(5):501-510
The proliferative activity of the cells of uterine epithelium and stroma of the developing golden hamsters and the activity of acid phosphatase isozymes in these tissues was studied. The dynamics of changes of these indices during the normal development and upon estrogenic stimulation was followed. The uterine cells were shown to react to estrogenic stimulation was followed. The uterine cells were shown to react to estrogenic stimulation by the increase of proliferation from the first days of postnatal development. Characteristic changes in the ratio of the acid phosphatase isozymes in the epithelial cells in response to estrogenic stimulation appeared in the 2nd week of postnatal development only. The definite level of differentiation of cells-targets appears to be indispensable for the realization of certain specific effects of the hormone.  相似文献   

9.
The effects of ethylenethiourea (ETU) were investigated using rat (Wistar-imamichi) embryos cultured from days 11 to 13 of gestation or cultured rat embryonic cells extracted on day 11. Malformations in cultured embryos at the concentration of 30 micrograms/ml of ETU were found in the head and tail, which were severely affected, as well as the limb and face. All embryos exposed to 150 and 300 micrograms/ml of ETU had malformed heads, tails, limbs, and facial configurations. Protein contents of the cultured embryos were decreased dose-dependently at the concentrations ranging from 30 to 300 micrograms/ml. In the histological studies of the cultured embryos with ETU, thinner neuroepithelium in head was observed. In the embryonic cells extracted on day 11 of gestation, ETU dose-dependently inhibited the differentiation of midbrain (MB) cells into neurons and that of limb bud (LB) cells into chondrocytes at the concentrations ranging from 30 to 600 micrograms/ml of ETU. The concentrations of ETU that inhibited the production of differentiated foci by 50% (IC50) were 170 micrograms/ml in LB cells of day 11, and greater than 600 micrograms/ml in LB cells on day 12 of development. Therefore, differentiation of MB cells was more sensitive to ETU than the differentiation of LB cells. These results indicated that there was a reasonable correlation of ETU induced changes in cultured whole embryos and embryonic cells.  相似文献   

10.
Only a small proportion of ewes at estrus have been found to respond maternally to newborn lambs, and this low maternal responsiveness may be partially attributable to the absence of the genital stimulation which occurs at parturition. Therefore, the effect of artificial genital stimulation on maternal behavior of estrous ewes was investigated. Estrus was synchronized in 33 ewes by placement and withdrawal of progestin-saturated vaginal sponges. Estrous ewes were divided into two groups, a control group and a group receiving 5 min of artificial genital stimulation, and observed following presentation of newborn lambs. Significantly more stimulated ewes licked the lamb and emitted low-pitched bleats in a 30-min test. When genital stimulation was subsequently administered to control ewes, more of them also became maternal so that the two groups were no longer significantly different. These results indicate that absence of genital stimulation is one of the factors contributing to the low maternal responsiveness of estrous ewes. They also demonstrate for the first time that artificial genital stimulation is effective in eliciting maternal behavior in nonpregnant ewes even at physiological concentrations of estradiol.  相似文献   

11.
目的 研究阿奇霉素治疗生殖道沙眼衣原体感染过程中对局部黏膜免疫反应的影响,为其临床应用提供新的实验依据.方法 构建小鼠生殖道沙眼衣原体感染模型,随机分为生理盐水组和阿奇霉素组.阿奇霉素组一次性给予阿奇霉素(80mg/kg),生理盐水组给予等量生理盐水.给药当天、给药第7天、给药第14天和给药第21天,阴道拭子取宫颈脱落细胞,分离沙眼衣原体.给药21天,处死动物.收集血清,ELISA测定血清IL-6和TNF-α水平,同时进行阴道、宫颈黏膜常规HE染色和肥大细胞甲苯胺蓝染色、树突状细胞免疫组织化学分析.结果 1.阿奇霉素组沙眼衣原体感染率明显低于生理盐水组,且未出现上行感染(P〈0.05).2.阿奇霉素组生殖道黏膜内树突状细胞数量增加(P〈0.05),肥大细胞数量无明显变化(P〈0.05).3.阿奇霉素组血清内IL-6和TNF-α的水平,均高于对照组和生理盐水组(P〈0.05).结论 阿奇霉素除了有效清除生殖道沙眼衣原体感染,亦可以调节生殖道黏膜的免疫反应,减轻免疫病理损伤,使沙眼衣原体感染有较好的预后.  相似文献   

12.
J E Embree  J A Embil 《CMAJ》1980,123(2):105-111
The roles of Mycoplasma pneumoniae, M. hominis and Ureaplasma urealyticum in diseases of humans are currently under investigation. M. pneumoniae, which causes primary atypical pneumonia, is a well established pathogen of the respiratory tract. Complications of infection by this organism are also being recognized; they include disorders of the hematopoietic, cardiovascular, central nervous, musculoskeletal, cutaneous and gastrointestinal systems. The roles of the genital mycoplasmas M. hominis and U. urealyticum are controversial but may include infections of the genitourinary tract and in pregnancy as well as diseases of the newborn, such as neonatal pneumonia and meningitis. In this review atypical pneumonia due to M. pneumoniae is described and the role of mycoplasmas in other diseases is discussed.  相似文献   

13.
A better understanding of the regulatory role of genital tract T cells is much needed. In this study, we have analyzed the phenotype, distribution, and function of T lymphocytes in the female genital tract of naive, pregnant, or Chlamydia trachomatis-infected C57BL/6 mice. Unexpectedly, we found that the dominant lymphocyte population (70-90%) in the genital tract was that of CD3(+)alphabetaTCR(int)CD4(-)CD8(-) T cells. Moreover, these cells were CD90(low) but negative for the classical T cell markers CD2 and CD5. The CD3(+)B220(low) cells were NK1.1 negative and found in nude mice as well as in mice deficient for MHC class II, beta(2)-microglobulin, and CD1, indicating extrathymic origin. They dominated the KJ126(+)Vbeta8.2(+) population in the genital tract of DO11.10 OVA TCR-transgenic mice, further supporting the idea that the CD3(+)B220(low) cells are truly T cells. The function of these T cells appeared not to be associated with immune protection, because only CD4(+) and CD8(+) T cells increased in the genital tract following chlamydial infection. Notwithstanding this, the infected, as well as the uninfected and the pregnant, uterus was dominated by a high level of the CD3(+)CD4(-)CD8(-)B220(low) cells. Following in vitro Ag or polyclonal stimulation of the CD3(+)CD4(-)CD8(-)B220(low) cells, poor proliferative responses were observed. However, these cells strongly impaired splenic T cell proliferation in a cell density-dependent manner. A large fraction of the cells expressed CD25 and produced IFN-gamma upon anti-CD3 plus anti-CD28 stimulation, arguing for a strong regulatory role of this novel T cell population in the mouse female genital tract.  相似文献   

14.
Chlamydial pathogenicity in the upper genital tract relies on chlamydial ascending from the lower genital tract. To monitor chlamydial ascension, we engineered a luciferase-expressing C. muridarum. In cells infected with the luciferase-expressing C. muridarum, luciferase gene expression and enzymatic activity (measured as bioluminescence intensity) correlated well along the infection course, suggesting that bioluminescence can be used for monitoring chlamydial replication. Following an intravaginal inoculation with the luciferase-expressing C. muridarum, 8 of 10 mice displayed bioluminescence signal in the lower with 4 also in the upper genital tracts on day 3 after infection. By day 7, all 10 mice developed bioluminescence signal in the upper genital tracts. The bioluminescence signal was maintained in the upper genital tract in 6 and 2 mice by days 14 and 21, respectively. The bioluminescence signal was no longer detectable in any of the mice by day 28. The whole body imaging approach also revealed an unexpected airway infection following the intravaginal inoculation. Although the concomitant airway infection was transient and did not significantly alter the genital tract infection time courses, caution should be taken during data interpretation. The above observations have demonstrated that C. muridarum can not only achieve rapid ascending infection in the genital tract but also cause airway infection following a genital tract inoculation. These findings have laid a foundation for further optimizing the C. muridarum intravaginal infection murine model for understanding chlamydial pathogenic mechanisms.  相似文献   

15.
The effects of hypophysectomy and gonadotropin replacement on transepithelial movement of 3H-androgen in the rat epididymis were examined by in vivo microperifusion of 3H-testosterone followed by in vivo micropuncture to obtain peritubular and intraluminal fluid. In the caput epididymidis of normal rats, intraluminal 3H-androgen concentrations were approximately 300% of those in the interstitial space. In contrast, proluminal movement of 3H-androgen into rat caput epididymal tubules was significantly decreased 10 days after hypophysectomy. 3H-Testosterone movement across the caput epididymal epithelium was completely returned to normal by supplementation with 24 micrograms/day follicle-stimulating hormone (FSH) or 24 micrograms/day luteinizing hormone (LH). However, neither 0.12 micrograms/day FSH nor 250 micrograms/day prolactin returned proluminal androgen movement to normal. It is speculated that epididymal uptake of peritubular testosterone is mediated by androgen-binding protein, which is known to be secreted by Sertoli cells after stimulation by FSH or testosterone.  相似文献   

16.
We have investigated whether the androgen-induced masculine differentiation of the sex organs involves an induction of phospholipases. We have measured phosphatidylinositol-specific phospholipase C and phosphatidylcholine-specific phospholipase A2 in the reproductive tract of male and female mouse (CD-I) fetuses at the 18th day of gestation. We report here that (1) the activity of these two enzymes is higher in the male genitalia than in the female genitalia; (2) exogenous testosterone at the 13th to 17th day of pregnancy induces both phospholipase A2 and phospholipase C in the female fetal genitalia; and (3) prenatal administration of cyproterone acetate, an antiandrogen, known to produce feminized males, completely prevents the stimulation of phospholipase A2 and C by testosterone in the female fetuses. In the male fetuses, however, cyproterone acetate inhibits the PLC activity but is unable to alter phospholipase A2 activity. These findings provide evidence that the mechanism by which testosterone organizes the genitalia may involve a modification of phospholipases A2 and C.  相似文献   

17.
The role of EGF in testosterone-induced reproductive tract differentiation   总被引:7,自引:0,他引:7  
EGF is known to modulate a variety of cellular functions including differentiation. The aim of this investigation was to determine the role of EGF in androgen-induced masculine differentiation. Accordingly, a series of experiments were designed and the results are summarized as described below. (1) We found that the specific deprivation of EGF using anti-EGF serum during the period of masculine differentiation in an organ culture bioassay system resulted in the disintegration of the Wolffian system in a dose-dependent manner. (2) Exogenous EGF supplemented in the above experiment corrected the anti-EGF effect, suggesting a specific role of EGF. (3) Anti-EGF serum was also found to disrupt the differentiation even in the presence of exogenous testosterone, suggesting an effect independent of testosterone synthesis. (4) EGF was found to have a direct masculinizing effect both in vivo and in vitro; however, it was not able to mimic all masculinizing effects of testosterone. The mesonephric segment of the Wolffian duct was retained by EGF in the female fetal tract under in vitro conditions, and under in vivo conditions EGF was able to increase anogenital distance and to induce epididymis in some female fetal mice. (5) We were able to detect an EGF-like material in the fetal genital tract during differentiation and found that the level of this material increased with advancement of differentiation. Thus, it appears from the above results that EGF plays a role in testosterone-induced reproductive tract differentiation.  相似文献   

18.
The biological basis for the observed modulation in cytoplasmic progesterone receptors (PgR) of normal mammary gland occurring during mammary development was investigated. Specifically, the relative roles of hormones vs. differentiation on (a) the decrease in PgR concentration during pregnancy and lactation and (b) the loss of mammary responsiveness to estrogen during lactation were examined. PgR were measured using the synthetic progestin, R5020, as the ligand. The hormones estrogen and progesterone were tested in vivo for their effect of PgR concentration. Mammary gland differentiation was assessed morphologically and by measuring enzymatically active alpha- lactalbumin. These studies show that there is a stepwise decrease in PgR that occurs in two stages. The first decrease is completed by day 12 of pregnancy and the second decrease occurs only after parturition. There appears to be a hormonal basis for the first decrease and it appears to be caused by the negative effect of progesterone on estrogen- mediated increase in PgR. In direct contrast, the absence of PgR during lactation and the mammary tissue insensitivity to estrogenic stimulation of PgR were not related to the hormonal milieu of lactation but were directly related to the secretory state of the mammary gland and lactation per se.  相似文献   

19.
Development of the response of the auditory cortex to unilateral acoustic stimulation by a chick was studied in guinea-pig foetuses from the 50th day to the end of gestation and in newborn animals. The first cortical response appeared on the 52nd to 53rd day of gestation. The maximum responses were concentrated in the temporal cortex, between the somatosensory (parietal) and optic (occipital) area. The progressive development of the latent period of the cortical response and of its various components distinctly slowed down on the last days of gestation. At the same time, the amplitude of the cortical response was temporarily augmented. The cortical response developed from a simple negative wave in the youngest embryos into an intricate complex with an initial positive component in newborn guinea-pigs. The basic components of this complex were already discernible on the 64th to 65th day of gestation. The ability to react to repeated peripheral stimulation of 0.1-2 c/s frequency increased with foetal age, with temporary deterioration on the last days of gestation. Resistance of the cortical auditory response to cerebral anoxia rose up to term, with a temporary drop from the 64th day of gestation. After the initiation of independent respiration, cerebral hypoxia and bilateral vagotomy chiefly influenced the stability of the more recent components of the cortical auditory response in mature foetuses.  相似文献   

20.
E A Ivanova 《Ontogenez》1976,7(4):401-405
The dynamics of testosterone-7alpha-3H consumption by the reproductive tract rudiments (tubules, urogenital sinus and genital tubercle) and the muscles has been studied in the in vitro experiments immediately after the isolation of embryos (16-21 days of development), as well as after the preliminary two days cultivation in the diffusion chambers (13-20 days of development). In the first series of experiments, the selective, specific consumption of the labelled androgen was observed at all stages under study, whereas in the second series of experiments the specific and selective consumption in the organs-targets was noted from the 15th day of development (in the genital tubercle and urogenital sinus). No selective consumption in the tubules was noted.  相似文献   

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