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1.
目的探讨雌(Estrogen,E2)、孕激素(Progesterone,P4)对同期发情与自然发情小鼠子宫内膜中孕激素受体(Progesterone receptor,PR)分布的影响。方法45只同日龄雌鼠,根据处理方式的不同随机分为5组:自然发情组(对照组)、同期发情组、卵巢摘除组、P4处理组和E2处理组,5组小鼠在见栓后第4、6、8天分别取样后,采用免疫组织化学法观察小鼠子宫内膜中PR的分布变化情况。结果免疫组织化学染色结果显示,5个处理组小鼠子宫内膜的三种细胞中都有PR存在;同期发情组小鼠子宫内膜中三种类型细胞PR的表达与自然发情组差异有显著性(P〈0.05);P4处理组小鼠子宫内膜中三种类型细胞PR的表达在见栓第4、6天显著低于卵巢摘除组(P〈0.05);E2处理组小鼠子宫内膜腺上皮和间质中PR在第4、6、8天时都显著高于卵巢摘除组(P〈0.05),而在腔上皮中则显著低于卵巢摘除组(P〈0.05)。结论同期发情处理与自然发情小鼠的子宫内膜上PR的分布,都受E2和P4的特异诱导而变化。  相似文献   

2.
目的HB-EGF过表达可促进心肌纤维化及心肌细胞凋亡,本文研究人参皂甙Rb1对cTnT^R141W转基因扩张型心肌病小鼠发病过程中的HB-EGF表达和心肌纤维化的影响。方法将cTnT^R141W转基因小鼠随机分为模型组和人参皂甙Rb1组(70 mg/kg/d),连续给药7个月,取野生型小鼠作为对照组。用Kaplan-Meier法进行生存分析。心脏超声检测心功能及心脏几何构型。计算心重指数。光镜观察心肌细胞及间质变化。Western blot检测心脏HB-EGF,pSTAT3表达水平。结果Rb1长期给药能显著改善该模型的心功能和心脏几何构型,将死亡率降低50%。Rb1治疗组心重指数降低11.3%(P〈0.05),光镜观察显示Rb1能减轻心肌细胞排列紊乱以及间质纤维化。Western blot结果显示Rb1能够显著降低模型中的HB-EGF及pSTAT3的表达。结论Rb1抑制心肌病发生中的HB-EGF表达及抑制下游信号pSTAT的激活,并改善扩张型心肌病模型的心功能及心脏重构。  相似文献   

3.
Ovarian carcinoma (OCa) continues to be the leading cause of death due to gynecologic malignancies and the vast majority of OCa is derived from the ovarian surface epithelium (OSE) and its cystic derivatives. Epidemiological evidence strongly suggests that steroid hormones, primarily estrogens and progesterone, are implicated in ovarian carcinogenesis. However, it has proved difficult to fully understand their mechanisms of action on the tumorigenic process. New convincing data have indicated that estrogens favor neoplastic transformation of the OSE while progesterone offers protection against OCa development. Specifically, estrogens, particularly those present in ovulatory follicles, are both genotoxic and mitogenic to OSE cells. In contrast, pregnancy-equivalent levels progesterone are highly effective as apoptosis inducers for OSE and OCa cells. In this regard, high-dose progestin may exert an exfoliation effect and rid an aged OSE of pre-malignant cells. A limited number of clinical studies has demonstrated efficacies of antiestrogens, aromatase inhibitors, and progestins alone or in combination with chemotherapeutic drugs in the treatment of OCa. As a result of increased life expectancy in most countries, the number of women taking hormone replacement therapies (HRT) continues to grow. Thus, knowledge of the mechanism of action of steroid hormones on the OSE and OCa is of paramount significance to HRT risk assessment and to the development of novel therapies for the prevention and treatment of OCa.  相似文献   

4.

Sensitization to psychostimulant drugs, as well as morphine, subjected to cross-sensitization with stress. The development of morphine sensitization is associated with enhancements in dopamine overflow in the Nucleus accumbens (NAc). This study aimed to examine the role of accumbal D1/D2-like dopamine receptors in restraint stress (RS) induced sensitization to morphine antinociceptive effects. Adult male Wistar rats weighing 220–250 g underwent stereotaxic surgery. Two stainless steel guide cannulae were bilaterally implanted, 1 mm above the NAc injection site. Different solutions of SCH-23390, as a D1-like receptor antagonist or sulpiride, as a D2-like receptor antagonist, were microinjected into the NAc five min before exposure to RS. Restraint stress lasted for 3 h, 10 min after RS termination; animals received a subcutaneous injection of morphine (1 mg/kg) for 3 consecutive days. The procedure was followed by a 5-day drug and/or stress-free period. After that, on the 9th day, the nociceptive response was evaluated by the tail-flick test. The results revealed that intra-NAc administration of D1/D2-like dopamine receptor antagonists, SCH-23390 or sulpiride, respectively, blocked morphine sensitization-induced by RS and morphine co-administration in rats for three consecutive days. This work provides new insight into the determinant role of accumbal dopamine receptors in morphine sensitization produced by RS-morphine co-administration.

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5.
目的:应激对胃肠动力有重要的影响,可引起肠易激综合征患者症状的发作或加重,本研究采用束缚-浸水应激诱导肠易激综合征模型小鼠,分别予以雌激素、孕激素和雌激素+孕激素处理,观察结肠动力学及NO含量指标,以探讨雌、孕激素能否改善应激诱发的结肠功能异常并探讨其调节机制,进从为临床治疗肠易激综合征提供理论依据.方法:建立束缚浸水应激诱发的肠易激综合征小鼠模型,制备离体结肠平滑肌肌条,应用张力换能器测定其肌张力,并检测其排便粪点数以观察结肠平滑肌动力,采用硝酸还原酶法测量结肠一氧化氮(NO)的含量.结果:束缚浸水应激刺激诱发结肠肌张力增加和NO含量减少,与模型组比较,雌激素可逆转该作用,而孕激素、雌激素+孕激素则使该作用增强.结论:雌孕激素可以通过调节NO含量变化影响束缚-浸水应激诱导的肠易激综合征结肠收缩活动.束缚-浸水应激导致肠易激综合征模型小鼠结肠动力学改变,表现为增强远端结肠平滑肌收缩活动,同时模型小鼠结肠NO含量降低;雌激素可以逆转结肠平滑肌收缩活动增强和结肠NO含量降低;孕激素、雌激素+孕激素使结肠平滑肌收缩活动增强和结肠NO含量降低作用更加明显.  相似文献   

6.
7.
Abstract

Experimental conditions for the optimal measurement of estrogen (ER) and progesterone (PR) receptors in normal vervet monkey (Cercopithecus aethiops pygerythrus) uteri are described. The uteri of this primate were found to contain relatively high concentrations of both ER and PR. Levels of ER ranged from 151 to 822 femtomoles per mg protein (mean for group assayed is 327±165 femtomoles per mg protein). PR assays were performed on the same cytosols and the levels ranged from 444 to 2267 femtomoles per mg protein (mean of 1285±511 femtomoles per mg protein). Mean Kd values for the ER- and PR-ligand complexes were found to be 3.15±1.4x10-10 M and 2.38±0.2x10-9 M respectively, within the group analysed (n=21). The ratio of PR to ER varied between 1.1 and 13.1 with a mean of 4.5±2.4. Ligand specificity studies revealed that [3H]-17β-estradiol binding to the ER could only be inhibited by estrogens or estrogen analogues. The PR however exhibited an affinity for a wider range of ligand types. In low ionic strength buffers both ER and PR sedimented as ±8S type molecules in the presence or absence of 10mM sodium molybdate. Both receptors dissociated into smaller components, following a short exposure to 0.4 M KCl and subsequent centrifugation in a gradient containing 0.4 M KCl.  相似文献   

8.
9.
It is known that some vertebrate reproductive hormones have effects on rotifer reproduction, but little is known about their effects in combination. This motivated us to examine the effects of waterborne progesterone (P), testosterone (T), and estradiol (E) on reproduction of the rotifer Brachionus calyciflorus, comparing exposures to single hormones and mixtures with a total concentration of 1000 μg/L. Asexual population growth (r) was high in all treatments, ranging from 1.28 to 1.43 d–1 (P‐E), and from 0.99 to 1.22 d–1 (P‐T). These results indicate that E, P, or T alone, or in combinations of P‐E and P‐T totaling 1000 µg/L, and the 3‐way combination P‐E‐T at 1200 µg/L do not reduce the asexual reproduction of B. calyciflorus. However, significant effects were detected on sexual reproduction with exposure to these hormone concentrations. Exposure to P‐T and P‐E at 1000 μg/L decreased resting egg production significantly. Analysis of mating indicated that fertilization was 5.3 times higher in the control than in treatments where females were exposed to 500 µg/L each P‐T. A similar result was observed when both females and males were exposed to 500 µg/L each of P‐T. When males alone were treated with 500 µg/L each of P‐T, there was no significant difference in male fertility compared to the control. These results suggest that B. calyciflorus uses oxidized sterols similar to P and T to regulate sexual reproduction and waterborne exposure of females to these compounds interferes with fertilization and resting egg production. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

10.
In addition to the classical nuclear estrogen receptor, the expression of non-nuclear estrogen receptors localized to the cell surface membrane (mER) has recently been demonstrated. Estrogen and its receptors have been implicated in the development or progression of numerous neurodegenerative disorders. Furthermore, the pathogenesis of these diseases has been associated with disturbances of two key cellular programs: apoptosis and autophagy. An excess of apoptosis or a defect in autophagy has been implicated in neurodegeneration. The aim of this study was to clarify the role of ER in determining neuronal cell fate and the possible implication of these receptors in regulating either apoptosis or autophagy. The human neuronal cell line SH-SY5Y and mouse neuronal cells in primary culture were thus exposed to chronic minimal peroxide treatment (CMP), a form of subcytotoxic minimal chronic stress previously that mimics multiple aspects of long-term cell stress and represents a limited molecular proxy for neurodegenerative processes. We actually found that either E2 or E2-bovine serum albumin construct (E2BSA, i.e. a non-permeant form of E2) was capable of modulating intracellular cell signals and regulating cell survival and death. In particular, under CMP, the up-regulation of mERα, but not mERβ, was associated with functional signals (ERK phosphorylation and p38 dephosphorylation) compatible with autophagic cytoprotection triggering and leading to cell survival. The mERα trafficking appeared to be independent of the microfilament system cytoskeletal network but was seemingly associated with microtubular apparatus network, i.e., to MAP2 molecular chaperone. Importantly, antioxidant treatments, administration of siRNA to ERα, or the presence of antagonist of ERα hindered these events. These results support that the surface expression of mERα plays a pivotal role in determining cell fate, and that ligand-induced activation of mER signalling exerts a powerful cell-survival signal. These results shed new light on the pathogenetic mechanisms leading to neuronal cell degeneration.  相似文献   

11.
12.
Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a member of the epidermal growth factor family and has a variety of physiological and pathological functions. Modulation of HB-EGF activity might have a therapeutic potential in the oncology area. We explored the therapeutic possibilities by characterizing the in vitro biological activity of anti-HB-EGF monoclonal antibody Y-142. EGF receptor (EGFR) ligand and species specificities of Y-142 were tested. Neutralizing activities of Y-142 against HB-EGF were evaluated in EGFR and ERBB4 signaling. Biological activities of Y-142 were assessed in cancer cell proliferation and angiogenesis assays and compared with the anti-EGFR antibody cetuximab, the HB-EGF inhibitor CRM197, and the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab. The binding epitope was determined with alanine scanning. Y-142 recognized HB-EGF as well as the EGFR ligand amphiregulin, and bound specifically to human HB-EGF, but not to rodent HB-EGF. In addition, Y-142 neutralized HB-EGF-induced phosphorylation of EGFR and ERBB4, and blocked their downstream ERK1/2 and AKT signaling. We also found that Y-142 inhibited HB-EGF-induced cancer cell proliferation, endothelial cell proliferation, tube formation, and VEGF production more effectively than cetuximab and CRM197 and that Y-142 was superior to bevacizumab in the inhibition of HB-EGF-induced tube formation. Six amino acids in the EGF-like domain were identified as the Y-142 binding epitope. Among the six amino acids, the combination of F115 and Y123 determined the amphiregulin cross-reactivity and that F115 accounted for the species selectivity. Furthermore, it was suggested that the potent neutralizing activity of Y-142 was derived from its recognition of R142 and Y123 and its high affinity to HB-EGF. Y-142 has a potent HB-EGF neutralizing activity that modulates multiple biological activities of HB-EGF including cancer cell proliferation and angiogenic activities. Y-142 may have a potential to be developed into a therapeutic agent for the treatment of HB-EGF-dependent cancers.  相似文献   

13.
14.
Adrenocorticotropin (ACTH) was administered to female rhesus monkeys in order to determine the effects of adrenal axis activation on the endocrine events occurring during the menstrual cycle. ACTH injected twice daily during the follicular period and through the time of expected ovulation was found to prevent the rise of estrogens during the follicular phase. In addition, the ACTH administration also blocked the preovulatory surge of LH, prevented the luteal rise of progesterone, and extended the length of the menstrual cycle.  相似文献   

15.
以小鼠肉瘤S180为模型 ,研究人血小板生成素 (TPO)在肿瘤基因治疗方面的价值 .在小鼠接种瘤细胞前 2周 ,或在接种肿瘤细胞同时 ,给小鼠注射 10 0 μgTPO表达质粒 (pcDNA3 hTPO) ,在 2周和 4周时肿瘤平均重量明显小于单纯质粒 (pcDNA3)注射和生理盐水对照组 (提前转导组P <0 0 5 ,同时转导组P >0 0 5 ) .当肿瘤移植量为 1× 10 6时 ,2周时肿瘤的重量依次分别为 1 75 6g、3 6 37g和 3 92 6g ;当肿瘤移植量为 1× 10 5,2周时肿瘤的重量依次分别为 0 5 76g、5 6 1g和 5 84g .在转导基因 2周时 ,移植 1× 10 5肿瘤细胞组有 4 10受试鼠完全未形成肿瘤或肿瘤的生长被中止在早期阶段 .流式细胞分析发现 ,TPO转导后 ,肉瘤内浸润淋巴细胞从以CD8+为主转变为以CD4 +或CD4 +CD8+为主 .不过 ,TPO转导对瘤细胞在体外的增殖无明显改变 .TPO转导鼠的血清对S180细胞在体外的生长速度也无影响 .推测T淋巴细胞参与了TPO基因转导所产生的抗肿瘤作用  相似文献   

16.
Bovine cytosol estrogen (ERC) and progesterone receptor (PRC) concentrations were measured simultaneously in various regions of the uterus and in ovarian stromal tissue in cows with cystic ovarian disease (follicular cysts), arid the concentrations compared with those in animals with normal cycles. In cystic ovarian disease, ERC concentrations in endometrium (550 fmol/mg cytosol protein (c.p.)) and in myometrium (405) were significantly higher than in control animals. Very high PRC contents were measured in the endometrium (3115) and myometrium (2761) of cows with cystic ovarian disease. In control animals, PRC concentrations in the endometrium and myometrium were significantly lower than in diseased animals. No statistical differences were observed in ERC or PRC contents between the endometrium and the myometrium in cows with cystic ovarian disease. ERC and PRC concentrations in the uterine cervix and ovaries were low compared to those detected in the uterus. Bovine serum estradiol-17ß concentrations were higher (p<0.001) in cows with cystic ovarian disease than in control animals in postpartum anestrus or during the normal estrous cycle. Serum sex hormone-binding globulin (SHBG) concentrations were of the same magnitude as in control cows during their estrous cycles. These findings show that long standing low endogenous progesterone and elevated estradiol concentrations in serum are associated with elevated ERC and PRC concentrations in bovine uterus.  相似文献   

17.
Ischemic preconditioning (IPC), comprising exposure to sub-lethal short term ischemic events, has been shown to exert adaptive responses in many organs including the brain, thus guarding against exacerbations of ischemia reperfusion (IR). However, the mechanisms involved in the early phase of such a protection remain elusive; hence, the present study aimed to investigate the modulatory effect of preconditioning against IR induced injury on infarct size, free radicals, inflammatory/anti-inflammatory markers, caspase-3 and heat shock protein (HSP)70 in the rat hippocampus. To this end, male Wistar rats were divided into 3 groups, (1) sham operated (SO) control; (2) IPC, animals were subject to 3 episodes of ischemia (5 min) followed by reperfusion (10 min), afterwards rats underwent ischemia (15 min) followed by reperfusion (60 min); (3) IR animals were subjected to 15 min global ischemia followed by 60 min reperfusion. IR produced cerebral infarction accompanied by an imbalance in the hippocampal redox status, neutrophil infiltration, elevation in tumor necrosis factor (TNF)-α and prostaglandin (PG)E2, besides reduction in interleukin (IL)-10 and nitric oxide (NO) levels. IPC reverted all changes except for PGE2; however, neither HSP70 nor caspase-3 expression was altered following IR or IPC. The current study points thus towards the activation of the antioxidant system, anti-inflammatory pathway, as well as NO in the early phase of preconditioning protection.  相似文献   

18.
目的利用Wistar大鼠烟雾吸入模型,观察被动吸烟对Wistar大鼠卵巢结构的影响,检测生殖激素水平,分析生殖内分泌的变化,为提倡生育期妇女避免被动吸烟提供新的理论依据。方法建立大鼠烟雾吸入模型。32只健康雌性Wistar大鼠,鼠龄(60±5)d,每只体重200~250g,随机分为空白对照组和实验组,每组16只。实验组吸烟3个月,对照组正常饲养。3个月后处死两组大鼠。酶联免疫吸附试验方法 (enzyme linkedimmunosorbent assay,ELISA)检测雌鼠血清中雌激素(estrogen,E2)、孕激素(progesterone,P4)的水平;常规石蜡切片,免疫组织化学SP法检测各组雌鼠卵巢雌激素受体(estrogen receptor,ER)、孕激素受体(progesterone receptor,PR)的表达情况。所得数据采用SPSS软件作统计学处理分析,比较各组间差异程度。结果①酶联免疫吸附试验结果 :吸烟3个月大鼠血清E2水平比空白对照组显著降低,其浓度值比较差异有显著性;吸烟3个月大鼠血清P4水平比空白对照组显著降低,其浓度值比较差异有显著性。②免疫组织化学结果 :ER主要表达在大鼠卵巢组织的各级生长卵泡的颗粒细胞的细胞核内,呈棕黄色颗粒状分布,卵泡膜细胞和间质细胞也有少量表达。吸烟3个月的大鼠卵巢组织中ER的表达显著低于空白对照组。PR主要表达在大鼠卵巢组织卵泡的颗粒细胞的细胞质和细胞核中,呈棕黄色颗粒状分布,吸烟3个月的大鼠卵巢组织中PR的表达显著低于空白对照组。结论①成功的建立了大鼠被动吸烟模型。②被动吸烟可使大鼠血清中E2及P4水平明显降低,使大鼠卵巢中ER及PR的表达减少,提示被动吸烟可破坏卵巢的功能,引起生殖内分泌失调。  相似文献   

19.
Bioactive lipid molecules as lysophosphatidic acid (LPA), prostaglandins (PG) and endocannabinoids are important mediators of embryo implantation. Based on previous published data we became interested in studying the interaction between these three groups of lipid derivatives in the rat uterus during the window of implantation. Thus, we adopted a pharmacological approach in vitro using LPA, DGPP (a selective antagonist of LPA3, an LPA receptor), endocannabinoids’ receptor selective antagonists (AM251 and AM630) and non selective (indomethacin) and selective (NS-398) inhibitors of cyclooxygenase-1 and 2 enzymes. Cyclooxygenase isoforms participate in prostaglandins’ synthesis. The incubation of the uterus from rats pregnant on day 5 of gestation (implantation window) with LPA augmented the activity and the expression of fatty acid amide hydrolase, the main enzyme involved in the degradation of endocannabinoids in the rodent uteri, suggesting that LPA decreased endocannabinoids’ levels during embryo implantation. It has been reported that high endocannabinoids are deleterious for implantation. Also, LPA increased PGE2 production and cyclooxygenase-2 expression. The incubation of LPA with indomethacin or NS-398 reversed the increment in PGE2 production, suggesting that cyclooxygenase-2 was the isoform involved in LPA effect. PGs are important mediators of decidualization and vascularization at the implantation sites. All these effects were mediated by LPA3, as the incubation with DGPP completely reversed LPA stimulatory actions. Besides, we also observed that endocannabinoids mediated the stimulatory effect of LPA on cyclooxygenase-2 derived PGE2 production, as the incubation of LPA with AM251 or AM630 completely reversed LPA effect. Also, LPA augmented via LPA3 decidualization and vascularization markers. Overall, the results presented here demonstrate the participation of LPA3 in the process of implantation through the interaction with other groups of lipid molecules, prostaglandins and endocannabinoids, which prepare the uterine milieu for embryo invasion during the window of implantation.  相似文献   

20.
In vivo imaging of cortical function requires optical access to the brain without disruption of the intracranial environment. We present a method to form a polished and reinforced thinned skull (PoRTS) window in the mouse skull that spans several millimeters in diameter and is stable for months. The skull is thinned to 10 to 15 μm in thickness with a hand held drill to achieve optical clarity, and is then overlaid with cyanoacrylate glue and a cover glass to: 1) provide rigidity, 2) inhibit bone regrowth and 3) reduce light scattering from irregularities on the bone surface. Since the skull is not breached, any inflammation that could affect the process being studied is greatly reduced. Imaging depths of up to 250 μm below the cortical surface can be achieved using two-photon laser scanning microscopy. This window is well suited to study cerebral blood flow and cellular function in both anesthetized and awake preparations. It further offers the opportunity to manipulate cell activity using optogenetics or to disrupt blood flow in targeted vessels by irradiation of circulating photosensitizers.  相似文献   

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