36 resultados para HORMONES

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Ab levels in the genital tract may be important in fertility and in preventing sexually transmitted diseases, In this study, I-125-labeled polymer or monomer mAb IgA (C4pIgA or C4mIgA) and IgC2b (C4IgC) to murine lactate dehydrogenase C4 and a polymer mAb IgA (npIgA) not cross-reacting with mouse sperm were intravenously injected into BALB/c mice, and the relative distribution of these Abs was determined. Polymer IgA was transported much more efficiently into the genital tract, trachea, and duodenum of both sexes than C4IgG and C4 mIgA (p < 0.01), The transport of polymer IgA (C4pIgA and npIgA) into the male genital tract greatly increased following orchiectomy (p < 0.01); this change was not affected by testosterone, suggesting that the unknown regulatory factor(s) from the testis may suppress polymer IgA transport, However, the transport of polymer IgA into female genital tissues was significantly decreased by ovariectomy (p < 0.01); this decline can be rectified by P-estradiol but not progesterone treatment, suggesting that estradiol may stimulate polymer IgA transport, Furthermore, the transport of C4IgG into tissues of the Fallopian tubes and the uterus was significantly decreased by treatment with progesterone (p < 0.01). Together, these findings indicate that serum polymer IgA can be transported selectively into the genital tracts of both sexes, that this transport is strongly under the control of gonads, and that transport of Ige into the Fallopian tubes and uterus is downregulated by progesterone.

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Antigen-specific circulating immunoglobulin-secreting cells (ISC) migrate to various secondary and tertiary lymphoid tissues. To understand the migration of the cells into the genital tract and its regulation by sex hormones, spleen-derived SG2 hybridoma cells secreting immunoglobulin G2b (IgG2b) and Peyer's patch-derived PA4 hybridoma cells secreting polymer IgA were labelled with (3) H-TdR, and intravenously injected into syngeneic mice of both sexes. Using flow cytometry, surface molecular markers of plasma cells, CD38 and CD138, and adhesion molecules, CD49d, CD162, and CD11a were found to be positive in SG2 and PA4 cells, but CD62L, alpha4beta7 and CD44 were not expressed on these cells. The relative distribution indexes (RDIs) of the cells in genital tract and other tissues were measured. The means of RDIs of SG2 and PA4 cells in female genital tissues were 6.5 and 4.5 times as many as the means in male genital tissues, respectively. The treatment of ovariectomized mice with beta-oestradiol significantly increased the RDIs of PA4 cells in cervix and vagina, but decreased the RDIs of SG2 cells in vagina, horn of uterus, uterus and rectum (P <0.05). Progesterone treatment increased the RDIs of PA4 cells in vagina and rectum (P <0.05). The treatment with testosterone significantly increased the RDIs of SG2 and PA4 cells in epididymis and accessory sex glands (P <0.05). These results demonstrate that the female genital tract is the preferable site for the migration of circulating hybridoma cells to the male genital tract, and sex hormones play an important role in regulation of the migration of circulating ISC to genital tracts.

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To understand better the molecular mechanisms of differential migration of antibody-secreting cells (ASCs) into mouse genital tracts, and regulation by sex hormones, surface markers, hormone receptors and adhesion molecules in mouse SG2 and PA4 hybridoma cells, respectively, secreting IgG2b and polymeric IgA antibody were detected by flow cytometry or RT-PCR. Semiquantitative RT-PCR was also used for measuring mRNA expression of adhesion molecules and chemokines (VCAM-1, ICAM-1, P-selectin, JAM-1 and CXCL12) in genital tracts of various adult mouse groups. The mRNAs of androgen receptor, estrogen receptor beta and CXCR4 were expressed in the ASCs. Sex hormones had no effect on expression of these molecules in ASCs. Except for VCAM-1, mRNA of all examined genes was expressed in normal mouse genital tracts. The mean of relative amounts of ICAM-1 and CXCL12 mRNA in all examined organs of females were higher (2.1- and 1.9-fold) than those in males. After orchiectomy or ovariectomy, the expression of ICAM-1, CXCL12 and P-selectin mRNA in the examined organs increased, except JAM-1 in male and CXCL12 in female. Sex hormone treatment recovered the changes to normal levels of mRNA expression in many examined genital tissues. In combination with our previous work, preferential migration of ASCs into female genital tract and regulation of migration by sex hormones are associated with expression patterns of adhesion molecules and chemokines in genital tract rather than in ASCs. (C) 2006 Elsevier Ireland Ltd. All rights reserved.

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The endocrine response of crucian carp injected intraperitoneally with extracted microcystins (MC) was investigated in this study. Fish were injected intraperitoneally either with 0.75% NaCl (control) and Microcystis extract corresponding to 150 and 600 mu g microcystins per kg body weight. The plasma levels of triiodothyronine (T-3), thyroxine (T-4), free triiodothyronine (FT3), free thyroxine (FT4), and cortisol were determined at 0, 1, 3, 12, 24. and 48 h post-administration of MC-containing extract. Treated fish displayed abnormal behaviors, Such as a startle response and disoriented swimming, as well as changes in ventilation rates. Plasma cortisol concentrations of fish in both dose groups significantly increased after administration of extracted MC and remained high throughout the experiment, which suggested that MC elicited a stress response in treated fish. The profiles of cortisol changes in treated fish appeared to be dose dependent, indicating that fish in the high dose group experienced greater MC-incluced disturbance. Mortality occurred after 12 h in the high dose group. Plasma levels of T-4, T-3, FT4, and FT3 did not vary significantly between the control fish. In contrast to this, fish exposed to MC-containing extract showed significant declines in T-3, FT4, and FT3 levels in a dose-depenclent manner throughout the experiment. Plasma T4 levels, however, did not vary significantly in the low dose group, whereas they decreased significantly it 48 h post injection in the high dose group. This study demonstrates that administration of microcystins-containing extract causes a stress response and reduces the plasma levels of thyroid hormones in crucian carp. These results illustrate that microcystins exerted potent effects on the endocrine system of crucian carp, through activating their hypothalamus-pituitary- interrenal axis and disturbing thyroid function. (c) 2008 Elsevier Ltd. All rights reserved.

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A method was presented for the determination of testosterone, methyltestosterone and progesterone in liquid cosmetics by coupling polymer monolith microextraction (PMME) to high performance liquid chromatography with UV detection. A poly (methacrylic acid-ethylene glycol dimethacrylate) monolithic capillary column was selected as the extraction medium, which showed high extraction capacity towards these compounds. To achieve optimum extraction performance, several parameters relating to PMME were investigated, including extraction flow rate and pH value, inorganic salt and organic phase concentration of the sample matrix. By simple dilution with phosphate solution and filtering, the sample solution then could be directly injected into the device for extraction. The limits of detection of testosterone, methyltestosterone and progesterone were calculated to be 2, 3, 2, 8 and 4.6 mu g/L. Good linearity was achieved in the range of 10 to 1000 mu g/L with a linear coefficient. r value above 0. 996. Excellent method reproducibility was found by intra- and inter-day precisions, yielding the relative standard deviations of < 7. 7 % and < 7. 5 %, respectively. Recovery for them in the real samples was between 83% and 119%.

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As a relatively isolated and unique freshwater population, the Yangtze finless porpoise (Neophocaena phocaenoides asiaeorientalis) is the most endangered subpopulation of this species. The objective of this study was to improve our understanding of their reproductive endocrinology by measuring (radioimmunoassay) serum concentrations of FSH, LH, estradiol (E-2), progesterone (P-4) and testosterone (T-2) in free-ranging animals. Blood samples were collected from 66 Yangtze finless porpoises (41 males and 25 females) captured in the middle and lower reaches of the Yangtze River. Based on significant variation of serum T-2 concentrations in males with body length (BL) > 138 cm, we inferred that they were mature; in these animals, there were significant seasonal variations in serum T-2 concentrations, with the highest concentrations in March and April (502.0 +/- 319.8 ng/dL, mean +/- S.D.) and the lowest in December (79.4 +/- 83.2 ng/dL). Serum T-2 concentrations positively correlated with serum concentrations of LH and weakly correlated with serum concentrations of E-2, whereas there was a significant negative correlation between serum LH and FSH concentrations in males > 138 cm. The smallest apparently pregnant female porpoise had a BL of 130 cm. Serum P-4 concentrations ranged from 13.2 to 112.4 ng/mL (43.9 +/- 28.3 ng/mL) in pregnant females, and fluctuated under 1.0 ng/mL in non-pregnant females with BL > 130 cm. Serum LH concentrations were significantly higher in non-pregnant females > 130 cm versus those females < 130 cm. To our knowledge, this is the first study of endocrine-related maturity and seasonal breeding characteristics of the Yangtze finless porpoise. (c) 2006 Elsevier Inc. All rights reserved.

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诱导风信子(Hyacnthus orientalis L.)同一花被外植体上不同部位细胞分化花芽,从外源激素的作用和内探激素的变化探讨细胞脱分化启动的原因,研究了不同外源激素的组合下同一花被不同部位花芽分化的诱导频率:测定了花被上、中,下三部位切块离体培养前后的内源IAA和Z+ZR的含量;在此之前研究了GC-MS.MIM内标法测定微量植物材料内源IAA含量的可行性. GC-MS.MIM内标法是测定微量(0.5-1g)植物材料内源IAA含量的一种比较理想的方法,所需材料量一般为0.58.这一方法的材料前处理采用粗提液用C18Sep-pak柱初步分离纯化.HPLC进一步纯化,能获得纯度高的样品,且操作简便,省时省力. 风信子同一花被不同部位细胞均能分化花芽.当培养基中附加2.0mg/l Zeatin或2.0mg/16-BAP时,随着外探IAA浓度从0升高到10.0mg/l.捆胞分化花芽的部位从花被下部向上部移动。 离体培养前后同一花被上、中、下三部位内源IAA和Z+ZR含量测定结果表明.风信子同一花被内源IAA含量是上部最高,下部次之,中部最低,而内源Z+ZR含量从上向下依次增加;在附加不同外源激素的MS培养基上培养3天后,同一花被上,中、下三部位内源IAA和Z+ZR含量部有一定的变化。

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预计到本世纪末,大气CO2浓度将会增加到540~970ppm,大气CO2浓度升高所引起的全球气候变化已经受到广泛的关注。植物生长依赖CO2,并且对大气CO2浓度升高在结构和生理上产生响应。目前已有大量报道,从生态系统、群落、种群、个体、器官、组织、生理以及生化等水平上研究高浓度CO2所对植物产生的影响。但是有关高浓度CO2对植物有性生殖影响的报道却很少,同时多数实验均建立在短期的生殖响应,忽视了植物在长期高CO2浓度下具有的反馈作用和CO2浓度变化对植物的驯化作用。植物有性生殖与其生态适应性和农作物籽粒产量的关系极为密切;同时,植物有性生殖特性的变化,也可作为预测植物对全球气候变化响应的重要指标之一。为此,利用高浓度CO2对植物进行长期选择实验将很有必要。研究结果将为预测未来大气CO2浓度增加的条件下陆地生态系统的演变趋势、全球变化对植物有性生殖响应的方式和机制提供新的思路和有效方法。   在本研究中,我们以模式植物拟南芥(Arabidopsis thaliana)作为实验材料,利用370和700ppm CO2对其进行连续8个世代处理,首先研究高浓度CO2对每一个世代的拟南芥有性生殖特性的影响,然后比较各个世代中各种生殖特性指标变化的规律,从细胞、组织和个体尺度上揭示拟南芥有性生殖对全球变化的响应模式。此外,在700ppm CO2处理下,我们对拟南芥叶片生理、生化以及结构的变化进行了相关研究。两部分研究结果及主要结论如下:   首先,在每一个世代中,与370ppm CO2相比较,700ppm CO2处理显著促进了拟南芥开花,缩短生长周期,增加花、角果及种子等生殖的产量,降低种子N含量,提高种子C/N比、种子千粒重以及生殖生物量所占总生物量的比例等,而对种子萌发率、角果所含种子数目以及角果长度则无显著影响。但是, 通过对相同CO2浓度处理条件下,不同世代之间的研究结果比较发现,不同世代之间相关的生殖生物学指标并无显著差异。   其次,高浓度CO2显著降低叶片气孔密度、气孔指数、气孔导度以及蒸腾速率。在高浓度CO2处理下,叶肉细胞中叶绿体数目、叶绿体宽度和表观面积、淀粉粒大小和数量、叶片和细胞壁厚度等都显著增加,但是基粒内囊体膜的数量却显著下降。叶片中碳水化合物如可溶性总糖、淀粉以及纤维素含量在高浓度CO2下分别显著增加71.9%、78.7% 和 22.3%。此外,在高浓度CO2处理下,叶片中多数激素如如吲哚乙酸(indole-3-acetic acid, IAA)、赤霉素(gibberellin, GA)、玉米素核苷(zeatin riboside, ZR)、二氢玉米素核苷(dihydrozeatin riboside, DHZR)和异戊烯基腺苷(isopentenyl adenosine, iPA)均都显著地增加,而脱落酸(abscisic acid, ABA)含量却有所下降。最后,叶片中各种矿物质元素含量如N、P、K、Ca和Mg等含量在高浓度CO2处理下也都显著下降,而C/N比增加24.8%。   以上结果表明:   (1) 在每一个世代中,700ppm CO2处理对拟南芥各种有性生殖特性具有显著的影响,但是高浓度CO2处理对植物所引起的效应在多个世代以内并不能够传递给后代,所以在多个有性生殖世代内,高浓度CO2处理对植物生长、生殖没有驯化作用。   (2) 在高浓度CO2处理下,拟南芥叶片中叶绿体超微结构的变化,可能主要是由于叶绿体中淀粉粒数量和体积大小显著增加而引起。   (3) 在高浓度CO2处理下,由于拟南芥叶片内与促进细胞分裂与伸长的激素含量显著增加,从而对拟南芥植株生长发育速率的提高起了重要的作用。   (4) 拟南芥生长在高浓度CO2条件下,其叶片中各种矿质元素含量(如N、P、K、Ca和Mg)均显著降低,究其原因可能是,第一由于叶片中碳水化合物含量的显著增加而对矿物质元素具有稀释作用;第二由于蒸腾速率下降,引起矿质元素从根部随着蒸腾流运输到地上部分的含量相应减少。   

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BACKGROUND: Effects of 17beta-estradiol and progesterone on rhesus monkey oocyte maturation in vitro were evaluated by embryo development subsequent to IVF. METHODS AND RESULTS: In experiment 1, immature cumulus-oocyte complexes collected from unstimulated adult females during the non-breeding season were matured in modified medium CMRL-1066 containing various combinations of gonadotrophins (FSH + LH), estradiol and/or progesterone. Formation of morulae and blastocysts was greatest in oocytes matured in medium containing estradiol and/or progesterone, with or without gonadotrophins (morula 38-46%, blastocyst 14-20%) than in control oocytes matured without estradiol or progesterone (morula 14%, blastocyst 0%). In experiment 2, cumulus-oocyte complexes from unstimulated prepubertal female monkeys were matured in medium with gonadotrophins, estradiol or progesterone. The best development to the morula stage was obtained with oocytes matured with gonadotrophins and estradiol or gonadotrophins and progesterone (43 and 25 morulae, respectively), while control oocytes matured with gonadotrophins but without steroid hormones gave the poorest morula developmental response (12%). However, there was no difference in blastocyst development across all groups (0-3%). CONCLUSIONS: These results demonstrate that during rhesus monkey oocyte maturation in vitro: (i) estradiol or progesterone can improve oocyte developmental competence; (ii) immature oocytes from prepubertal versus adult females have differential responses to challenge with estradiol or progesterone.

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Pituitary growth hormone (GH), like several other protein hormones, shows an unusual episodic pattern of molecular evolution in which sustained bursts of rapid change are imposed on long periods of very slow evolution (near-stasis). A marked period of rap

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 目的:探讨性激素调控抗体分泌细胞游走到生殖道的分子机制和对局部抗体分泌的影响。方法:以鼠源杂交 瘤细胞SG2 和PA4 为对象,检测其性激素受体、CXCR4 的mRNA 和CD31 的表达;用流式细胞术和ELISA 检测不同浓度性激素 作用下,抗体分泌细胞表面与细胞游走相关分子的表达和抗体分泌的变化。结果:SG2 和PA4 细胞表达雄激素受体和雌激素 受体β,表达CXCR4 ,但不表达CD31。性激素对抗体分泌细胞表面分子的表达和抗体分泌量并没有明显的影响。结论:性激素 对抗体分泌细胞游走的调控作用与细胞自身相关黏附分子的变化关系不大,推测可能主要是通过对内皮细胞地址素表达的 影响来实现的。

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Sertoli cells play a central role in the control and maintenance of spermatogenesis. Isolated Sertoli cells of mouse and rat testes have been shown to secrete plasminogen activator (PA) and a plasminogen activator inhibitor type-1 (PAI-1) in culture. In this study, we have investigated the hormonal regulation of PA and PAI-1 activities in cultured monkey Sertoli cells. Sertoli cells (5x10(5) cells/well) isolated from infant rhesus monkey testes were preincubated at 35 degrees C for 16 h in 24-well plates precoated with poly(D-lysine) (5 mu g/cm(2)) in 0.5 mi McCoy's 5a medium containing 5% of fetal calf serum and further incubated for 48 h in 0.5 mi serum-free medium with or without various hormones or other compounds, PA as well as PAI-1 activities in the conditioned media were assayed by fibrin overlay and reverse fibrin autography techniques respectively. The Sertoli cells in vitro secreted only tissue-type PA (tPA), no detectable amount of urokinase-type PA (uPA) could be observed, Monkey Sertoli cells were also capable of secreting PAI-1, Immunocytochemical studies indicated that both tPA and PAI-1 positive staining localized in the Sertoli cells, spermatids and residual bodies of the seminiferous epithelium; Northern blot analysis further confirmed the presence of both tPA and PAI-1 mRNA in monkey Sertoli cells. Addition of follicle-stimulating hormone (FSH) or cyclic adenosine monophosphate (cAMP) derivatives or cAMP-generating agents and gonadotrophin-releasing hormone (GnRH) agonist or phorbol ester (PMA) to the cell culture significantly increased tPA activity. PAI-1 activity in the culture was also enhanced by these reagents except 8-bromo-dibutyryl-cAMP, forskolin and 3-isobutyl-1-methylxanthin (MIX) which greatly stimulated tPA activity, whereas decreased PAI-1 activity, implying that neutralization of PAI-1 activity by tile high level of tPA in the conditioned media may occur. These data suggest that increased intracellular signals which activate protein kinase A (PKA), or protein kinase C (PKC) can modulate Sertoli cell tPA and PAI-1 activities, The concomitant induction of PA and PAI-1 by the same reagents in the Sertoli cells may reflect a finely tuned regulatory mechanism in which PAI-1 could limit the excession of the proteolysis.

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Testosterone undecanoate (TU) is under phase III clinical trial as a hormonal male contraceptive in China. Sex hormones can modulate the immune system. Female hormonal contraceptives may affect SIV/HIV-1 transmission. To evaluate the safety of TU and to understand whether long-term use of TU for a male contraceptive affects users' immunological features, adult male rats were treated for a 32-week TU-treated phase at the dose of 20 mg TU/kg body weight and a 24-week recovery phase. The reproductive and immunological parameters of 4-6 rats in each subgroup were examined at the stated time point. The mean sperm count and viability in the treated rats were significantly suppressed (p < 0.01). In the TU-treated group: the mean blood leukocyte and lymphocyte counts; the proliferation indexes of T cells from peripheral blood mononuclear cells (PBMC) and spleen; and, of B cells from spleen, as well as the mean counts of blood T, NK, and B cells decreased in comparison with those of control group. These decreases were not significant (p > 0.01). Similarly, the mean serum IgM, IgG, and IgA levels and complement activity in TU-treated rats were lower than those in control group (p > 0.01), and the changes in the antibody levels of the examined genital secretions were not significant (p > 0.01). The changes in the thickness of urethra epithelium, and in secretory component (SC) expression in genitals were not observed in the treated group. These results demonstrated that long-term supraphysiological TU injection did not obviously affect the examined rat immunological parameters.