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1.
旨在研究Ghrelin对产蛋鸡等级前卵泡发育的调节作用.通过RT-PCR方法检测卵泡Ghrelin受体(GH-SR)的表达情况,采用组织学和免疫组化方法探讨Ghrelin和促卵泡素(FSH)单独或联合处理对鸡等级前卵泡形态学的变化以及层粘连蛋白(LN)和缝隙连接蛋白43(Cx43)的标记率.结果表明,GHSR在颗粒层和膜层上均有表达,其表达量随着卵泡的发育分别至大白卵泡(LWF)和小黄卵泡(SYF)达到最高,随后逐渐降低.悬浮培养的卵泡经Ghrelin和FSH处理24 h后,LWF和SYF的颗粒层和膜层厚度及颗粒细胞密度均显著增加(P<0.05).同时,颗粒细胞中LN和Cx43的标记率显著提高(P<0.05),且以Ghrelin与FSH联合处理组最为显著.结果提示,Ghrelin可通过提高LN和Cx43的表达以增强颗粒细胞的连接功能,促进鸡等级前卵泡颗粒细胞的增殖,并可协同FSH调节卵泡的发育.  相似文献   

2.
探讨了前列腺素PGF2α类似物氯前列烯醇(Cloprostenol,CLO)对鸡等级前小黄卵泡颗粒细胞增殖的作用及其信号转导途径。颗粒细胞经16 h预培养后用CLO处理24 h,测定细胞的增殖情况。结果显示:0.1~10μg/L的CLO促进了颗粒细胞的增殖,10μg/L时刺激效果最为明显。蛋白激酶A(PKA)激活后颗粒细胞数量增加,PKA抑制剂H89抑制了CLO的促增殖作用。PKC的激活或抑制对CLO的促增殖作用无显著影响。这表明,CLO可通过PKA途径促进鸡等级前小黄卵泡颗粒细胞的增殖。  相似文献   

3.
为探索番鸭等级前卵泡发育过程中主要生殖激素及卵泡发育的变化规律,试验以同批孵化、饲养条件相同、体况相近的产蛋期番鸭为对象,分别采集小白卵泡(SWF)、大白卵泡(LWF)、小黄卵泡(SYF)、大黄卵泡(LYF)。通过组织形态学方法观测卵泡的发育情况,酶联免疫吸附试验(ELISA)测定激素水平。结果表明:在等级前卵泡发育过程中,促卵泡素(FSH)和促黄体素(LH)呈现上升的趋势,且LYF时期浓度最高,差异不显著(P0.05);而孕酮(P4)和雌二醇(E2)均呈现下降趋势,从SWF至SYF时期极显著下降(P0.01),SYF至LYF时期,下降不显著(P0.05)。伴随卵泡的发育,颗粒细胞层和卵泡膜层不断增厚,且卵泡膜厚度在LWF至LYF时期增长极显著(P0.01)。由此可见,FSH、LH、P4、E2在番鸭等级前卵泡发育中起重要作用,且SYF阶段是番鸭等级前卵泡发育的关键阶段。  相似文献   

4.
利用产蛋鸡小黄卵泡膜细胞培养模型研究黄体生成素(LH)对等级前发育的小黄卵泡膜细胞增殖的影响以及LH作用的信号转导途径。单层培养的外层膜细胞用LH(0.1~100μg/L)、蛋白激酶A(PKA)激活剂forskolin(FRSK,0.1~10μmol/L)及抑制剂H89(0.01~1μmol/L)或蛋白激酶C(PKC)激活剂佛波酯(PMA,0.1~10nmol/L)及抑制剂H7(0.01~1μmol/L)单独或共同处理,36 h后测定膜细胞增殖的变化。结果显示,LH和FRSK促进小黄卵泡膜细胞的增殖,且LH的促增殖作用可被H89阻断,而PMA无显著的促进作用,且H7不能阻断LH的促增殖作用。由此推断LH的促小黄卵泡外层膜细胞增殖作用主要是通过PKA途径进行的。  相似文献   

5.
鹅卵巢中含有众多的卵泡,产蛋期卵巢中总存在陆续成熟、大小不等的卵泡。卵泡壁由颗粒层和膜层组成,中以基膜相隔。颗粒层成于颗粒细胞。卵泡膜有成纤维细胞和分泌细胞,两种细胞混杂在一起,以至于卵泡膜的内外层分界不清,且在卵泡膜外层含有典型的平滑肌细胞。禽类产蛋性能主要由发育至等级发育阶段的卵泡数决定,而促进卵泡发育的等级与阶段主要取决于体外激素的分泌。  相似文献   

6.
本研究旨在探究促卵泡素(follicle stimulating hormone,FSH)处理对体外培养的牛有腔卵泡颗粒细胞和膜细胞类固醇激素合成相关基因表达的影响。采集牛卵巢表面直径9~11 mm的有腔卵泡,用含不同浓度FSH的DMEM/F12体外培养牛有腔卵泡24 h。提取卵泡颗粒细胞、膜细胞RNA并反转录成cDNA,利用实时荧光定量PCR检测卵泡颗粒细胞、膜细胞中类固醇激素合成酶基因(CYP11A1、3β-HSD、CYP17A1、CYP19A1、17β-HSD)和促性腺激素受体基因(FSHR、LHR)的表达水平。结果显示,FSH处理上调了颗粒细胞中CYP11A1、3β-HSDCYP19A1基因表达,其中,25 ng/mL FSH处理极显著上调了CYP11A1基因表达(P<0.01),10 ng/mL FSH处理显著上调了3β-HSD基因表达(P<0.05),50 ng/mL FSH处理显著上调了CYP19A1基因表达(P<0.05);50 ng/mL FSH处理显著或极显著上调了膜细胞中CYP11A1、3β-HSDCYP17A1基因表达(P<0.05;P<0.01),但在10和25 ng/mL FSH处理组中CYP11A1、3β-HSDCYP17A1基因表达显著或极显著下调(P<0.05;P<0.01)。对FSHR、LHR基因研究结果显示,不同浓度FSH处理对颗粒细胞中FSHR、LHR基因的表达均无显著影响(P>0.05),只有25和50 ng/mL FSH处理显著或极显著上调了膜细胞中LHR基因表达水平(P<0.05;P<0.01),且不同处理组之间膜细胞中CYP11A1、3β-HSDCYP17A1基因的表达变化与LHR基因表达变化趋势较一致。结果表明,FSH处理可提高牛有腔卵泡颗粒细胞中CYP11A1、3β-HSDCYP17A1基因的表达,膜细胞中CYP11A1、3β-HSDCYP17A1基因对LH的刺激更敏感,FSH可能通过影响LHR基因的表达来调节膜细胞中类固醇合成酶基因的表达。  相似文献   

7.
小白鼠卵泡壁发育的形态学研究   总被引:2,自引:0,他引:2  
选择性成熟的纯种小白鼠,用FSH和hcG处理,取其卵巢,制成光学切片,显微镜下观察卵泡壁发育的形态学变化过程。胚胎阶段发育而来的原始卵泡的扁平细胞钭发育为颗粒层细胞,颗粒细胞最初在单层上增殖细胞的数量;卵泡膜在初级卵泡在初期就开始形成,是由卵巢基质中的扁平样细胞发育而来;卵泡膜中的血管是由卵巢基质中血管伸入形成,在初级卵泡刚开始形成时就开始生长发育。  相似文献   

8.
颗粒细胞对卵泡发育的影响   总被引:3,自引:1,他引:2  
卵泡发育是一个复杂的生理过程,通过间隙连接,颗粒细胞在卵母细胞的生长发育过程中起营养作用,并促进卵母细胞的成熟;颗粒细胞和膜细胞的相互作用是卵泡发育和维持正常功能的重要条件。作为卵泡发育的标志,颗粒细胞的生长分化是原始卵泡启动和生长的关键,并通过受体介导途径调控生长期卵泡的发育及卵泡闭锁,从而在卵泡发育过程中起重要的调控作用。  相似文献   

9.
前列腺素对禽类等级卵泡发育的影响   总被引:3,自引:1,他引:2  
前列腺素是一类由花生四烯酸通过环氧化酶途径合成的脂类介导物。在哺乳动物排卵、受精、胚泡植入、蜕膜化、子宫平滑肌收缩、黄体退化及卵泡发育过程中起重要作用。对于家禽,前列腺素促进其产卵和子宫收缩;在产卵中期,卵巢静脉血浆中前列腺素的浓度为外周血浆浓度的5~20倍。这种高剂量、脉冲式分泌的前列腺素不仅能促进家禽成熟卵泡的排卵,而且可作为促性腺激素的第二信使介导颗粒细胞对cAMP的反应,促进了等级前卵泡颗粒细胞的增殖,进而在优势卵泡的选择过程中起重要作用。  相似文献   

10.
本研究旨在探究促卵泡素(follicle stimulating hormone,FSH)处理对体外培养的牛有腔卵泡颗粒细胞和膜细胞类固醇激素合成相关基因表达的影响。采集牛卵巢表面直径9~11 mm的有腔卵泡,用含不同浓度FSH的DMEM/F12体外培养牛有腔卵泡24 h。提取卵泡颗粒细胞、膜细胞RNA并反转录成cDNA,利用实时荧光定量PCR检测卵泡颗粒细胞、膜细胞中类固醇激素合成酶基因(CYP11A1、3β-HSD、CYP17A1、CYP19A1、17β-HSD)和促性腺激素受体基因(FSHR、LHR)的表达水平。结果显示,FSH处理上调了颗粒细胞中CYP11A1、3β-HSD和CYP19A1基因表达,其中,25 ng/mL FSH处理极显著上调了CYP11A1基因表达(P0.01),10 ng/mL FSH处理显著上调了3β-HSD基因表达(P0.05),50 ng/mL FSH处理显著上调了CYP19A1基因表达(P0.05);50 ng/mL FSH处理显著或极显著上调了膜细胞中CYP11A1、3β-HSD和CYP17A1基因表达(P0.05;P0.01),但在10和25 ng/mL FSH处理组中CYP11A1、3β-HSD和CYP17A1基因表达显著或极显著下调(P0.05;P0.01)。对FSHR、LHR基因研究结果显示,不同浓度FSH处理对颗粒细胞中FSHR、LHR基因的表达均无显著影响(P0.05),只有25和50 ng/mL FSH处理显著或极显著上调了膜细胞中LHR基因表达水平(P0.05;P0.01),且不同处理组之间膜细胞中CYP11A1、3β-HSD和CYP17A1基因的表达变化与LHR基因表达变化趋势较一致。结果表明,FSH处理可提高牛有腔卵泡颗粒细胞中CYP11A1、3β-HSD和CYP17A1基因的表达,膜细胞中CYP11A1、3β-HSD和CYP17A1基因对LH的刺激更敏感,FSH可能通过影响LHR基因的表达来调节膜细胞中类固醇合成酶基因的表达。  相似文献   

11.
A peptidyl-prolyl isomerase, Pin 1, has been shown to play a role in the regulation of cell cycle progression, both in vitro and in vivo. However, the involvement of Pin 1 during follicular development is not well understood. The aim of this study was first to investigate the expression of Pin 1 mRNA in the granulosa and theca cells of the follicle at different developmental stages of follicles in the bovine ovary, and second, to examine the effects of follicle-stimulating hormone (FSH) and estradiol (E2) on the expression of Pin 1 in the cultured bovine granulosa cells. Follicles were classified into four groups based on the diameter (dominant follicles >8.5mm in diameter, subordinate follicles <8.5mm in diameter) and the relative levels of E2 and progesterone (P4) (E2:P4>1, estrogen active; E2:P4<1, estrogen inactive): i.e. preovulatory dominant follicles (POFs); E2 active dominant follicles (EADs); E2 inactive dominant follicles (EIDs); small follicles (SFs). The expression of the Pin 1 gene was significantly increased in the granulosa cells of EADs as compared with those of other follicles, whereas its expression in theca cells did not differ among follicles at different developmental stages. The concentration of 5 ng/ml FSH alone and the combination of 1 ng/ml E2 and 5 ng/ml FSH stimulated the expression of the Pin 1 gene in bovine granulosa cells. Our data provide the first evidence that Pin 1 expression in the granulosa cells but not the theca cells changes during follicular development, and that FSH stimulate the expression of the Pin 1 gene. These results suggest that Pin 1 regulates the timing of cell proliferation and may act as an intracellular signal responder in the granulosa cells during bovine follicle development.  相似文献   

12.
Adiponectin and its receptors (AdipoR1 and AdipoR2) mRNAs are expressed in various chicken tissues including ovary. However, the cellular expression and the role of adiponectin system have never been investigated in chicken ovary. Here, we have shown that the level of adiponectin mRNA is about 10- to 30-fold higher (p < 0.001) in theca cells than in granulosa cells from each hierarchical yellow follicle studied (F4–F1). In contrast, the level of AdipoR1 mRNA expression was about two-fold lower in theca cells than in granulosa cells (p < 0.05) whereas those of AdipoR2 was similar in both ovarian cells. Whereas expression of adiponectin mRNA increased with follicular differentiation in theca cells, it decreased in granulosa cells. In contrast, mRNA expression of AdipoR1 and AdipoR2 in both theca and granulosa cells remained stable during yellow follicle development. To determine whether adiponectin is involved in the ovarian steroidogenesis, LH (100 ng/ml)-, FSH (100 ng/ml)- and IGF-1 (100 ng/ml)-induced progesterone production was measured in absence or presence of human recombinant adiponectin (10 μg/ml) for 36 h in cultured granulosa cells from F1, F2 and mixed F3 and F4 follicles. In absence of LH, FSH and IGF-1, adiponectin treatment had no effects on progesterone production whatever vitollegenic follicle studied. However, it increased by about two-fold IGF-1-induced progesterone secretion in F2 and F3/4 follicles whereas it halved progesterone production in response to gonadotropins (LH and FSH) in F3/4 follicles. Thus, in chicken, adiponectin, mainly expressed in theca cells, could exert paracrine or autocrine effect on the ovarian steroidogenesis.  相似文献   

13.
As stage progresses in the cystic follicle, granulosa cells are lost. We hypothesized that the granulosa and theca interna layers are detached in association with weakened expression of cell adhesion molecules such as cadherin (cell–cell adhesion) and integrin (cell–extracellular matrix adhesion) in cystic follicles. To elucidate this hypothesis, we immunolocalized these molecules in the granulosa and theca interna and compared them between cystic and small healthy follicles. Sections were immunostained with cadherin and integrin β1 antibodies and their localizations were compared. Cadherin‐positive reaction was seen in the cytoplasma of all granulosa cells. No increase in the frequency of cadherin‐positive area in the granulosa layers and the intensity of cadherin immunoreaction in the theca interna was detected in cystic follicles compared with healthy ones. A dense immunoreaction product of integrin β1 was detected in the theca interna in both cystic and healthy follicles. Intensity of integrin β1‐immuno reaction in the granulosa layers and integrin β1‐positive area in the theca interna was significantly lower in the cystic follicle than in the healthy follicles. These results suggest that granulosa and theca interna cells are detached while maintaining the cell–cell adhesion, resulting in the consequent loss of these layers from the cystic follicle.  相似文献   

14.
The aim of the present study was to examine the frequencies of cell proliferation and death of granulosa and theca interna layers during development of cystic follicles in order to understand the mechanisms of cystic follicle formation. Paraffin sections of cystic follicles were immunostained with antibodies against proliferating cell nuclear antigen (PCNA) and cleaved caspase-3 in order to observe proliferating and apoptotic cells, respectively. The concentrations of estradiol-17beta and progesterone in the follicular fluid of these follicles were measured by ELISA. The granulosa and theca interna layers contained both PCNA- and caspase-3-positive cells, although their numbers were limited. There was significant negative correlation between the estradiol-17beta and progesterone concentrations in the follicular fluid. Regression analysis revealed no significant correlation, except for that between the PCNA-positive cells in the theca interna and the caspase-3-positive cells in the granulosa layer. These results indicate that the granulosa and theca interna cells of the cystic follicle show weak proliferative activity and low apoptotic frequency; this implies that the cystic follicle grows slowly and then maintains a static condition without degeneration, which leads to long-term persistence of the follicle.  相似文献   

15.
The aim of this study was to examine the distribution of microvessels in the theca and the expression of vascular endothelial growth factor (VEGF) in the theca and granulosa of cystic follicles. Paraffin sections of cystic follicles were stained with Bandeiraea simplicifolia-I (BS-I) to visualize the endothelial cells of microvessels. The other sections were immunostained with anti-VEGF antibody. The mRNA expression of VEGF in the theca interna of cystic and healthy follicle was determined by RT-PCR. In the theca interna, cystic follicles with granulosa cells had significantly greater microvessel number density (the number of microvessels per given field) and area (area occupied by microvessels per given area) than healthy follicles in various sizes (<3, 4–8, >9 mm). Loss of granulosa cells from cystic follicles resulted in a similar number density, but significantly smaller area of microvessels in the theca interna. There was no significant difference in the microvessel number density and area of the theca externa between the types of follicle. VEGF protein was expressed in the granulosa and theca interna of healthy and cystic follicles. These results demonstrate that cystic follicles have a highly developed vasculature network in the theca interna, especially in cystic follicles containing granulosa cells. It is also suggested that VEGF is highly expressed in the cystic follicle as well as healthy follicle, which may be associated with advanced vasculature and the accumulation of follicular fluid in cystic follicles.  相似文献   

16.
Ovaries contain follicles at various stages of development, including primordial, primary, secondary, antral and Graafian follicles. Although the growth of these follicles is controlled to maintain regular ovulation, the mechanism through which this occurs remains unclear. In our study, we found that the growth rate of cultured secondary follicles separated from mice ovaries differed between follicles. After 4 days of culture, the size of some secondary follicles was markedly increased, while that of others had either slightly increased, remained unchanged or shrunk. We compared the expression levels of growth factors between these secondary follicles and found that the growth rate of cultured secondary follicles correlated with the expression level of insulin-like growth factor 1 (Igf1) mRNA. Igf1 mRNA expression level in secondary follicles containing theca cells was higher than that in secondary follicles without theca cells, and the granulosa cell proliferation around follicles containing theca cells was increased. Furthermore, an IGF1 inhibitor also inhibited the granulosa cell proliferation, and administration of IGF1 to secondary follicles without growth promoted granulosa cell proliferation. These results indicated that the theca cells of secondary follicles induced the expression of IGF1 and promoted the follicle growth.  相似文献   

17.
Cystic follicle is anovulatory follicular structure that is caused by an endocrine imbalance. The activity of cytochrome P450‐side chain cleavage (P450scc) is essential for the initiation of steroidogenesis in the follicle. The present study was designed to compare the frequency of cells containing P450scc between healthy and atretic small antral follicles, and among several types (I, II and III, classified based on the presence of granulosa layer) of cystic follicles. Paraffin sections of healthy (2–5 mm in diameter), atretic (2–5 mm) and cystic follicles (>25 mm) were immunohistochemically stained with rabbit polyclonal antibody to bovine P450scc. The P450scc‐positive cells were counted in four different regions of the follicles from the apical to the basal side. In small antral follicles and cystic follicles, P450scc‐positive cells were localized in the theca interna layers but not granulosa layers. The P450scc‐positive cell populations decreased in the late atretic follicles compared with the early and advanced atretic follicles at all the regions of follicle. Type III cystic follicles showed significantly lower frequencies of P450scc‐positive cells than those in the types I and II cystic follicles. These results suggest that in both small and cystic follicles in cows, total loss of granulosa cells may be associated with the reduction of frequency of P450scc‐positive cells in theca interna layer.  相似文献   

18.
In the mammalian ovary, aquaporins (AQPs) are thought to be involved in the regulation of fluid transport within the follicular wall and antrum formation. Data concerning the AQPs in the avian ovary is very limited. Therefore, the present study was designed to examine whether the AQP4 is present in the chicken ovary, and if so, what is its distribution in the ovarian compartment of the laying hen. Localization of AQP4 in the ovarian follicles at different stage of development was also investigated. After decapitation of hens the stroma with primordial follicles and white (1–4 mm), yellowish (4–8 mm), small yellow and the three largest yellow pre‐ovulatory follicles F3‐F1 (F3 < F2 < F1; 20–36 mm) were isolated from the ovary. The granulosa and theca layers were separated from the pre‐ovulatory follicles. The AQP4 mRNA and protein were detected in all examined ovarian compartments by the real‐time PCR and Western blot analyses, respectively. The relative expression of AQP4 was depended on follicular size and the layer of follicular wall. It was the lowest in the granulosa layer of pre‐ovulatory follicles and the highest in the ovarian stroma as well as white and yellowish follicles. Along with approaching of the largest follicle to ovulation the gradual decrease in AQP4 protein level in the granulosa layer was observed. Immunoreactivity for AQP4 was present in the granulosa and theca cells (theca interna ≥ theca externa > granulosa). The obtained results suggest that AQP4 may take part in the regulation of water transport required for follicle development in the chicken ovary.  相似文献   

19.
It has been hypothesized that the physiological basis of follicle selection is the differential expression of factors, which modulate the action of gonadotrophins on follicular cells, at key points during the process of follicle development. The aim of this research was to test this hypothesis by identifying factors that can enhance or attenuate the action of the gonadotrophins in stimulating follicle development using both in vivo and in vitro models. Experiments in vivo utilized sheep with an ovarian autotransplant to allow intra-arterial infusion of putative local factors and exposure of the ovary to high local concentrations. Experiments in vitro utilized physiological serum-free cell culture systems for both granulosa and theca cells that allow gonadotrophin-induced differentiation in vitro. The putative local factors tested included insulin-like growth factor-I (IGF-I LR3 analogue), transforming growth factor alpha (TGF alpha) or epidermal growth factor (EGF) and inhibin A. IGF-I stimulated both cellular proliferation and hormone production by both granulosa and theca cells in vitro and similarly stimulated ovarian follicle development and ovarian androgen and oestradiol secretion in vivo. Both TGF alpha and EGF stimulated granulosa and thecal cell proliferation in vitro in a dose-responsive manner and concomitantly inhibited hormone production, whereas intra-arterial infusion of TGF alpha in vivo resulted in induction of atresia in large antral follicles and an acute fall in ovarian hormone secretion. Inhibin A in vitro augmented gonadotrophin stimulated androgen and oestradiol production by thecal and granulosa cells, respectively, but had no effect on cell number. Paradoxically, intra-arterial infusion of inhibin A resulted in an acute depression in ovarian steroid secretion. This depression, however, was also associated with an acute depression in circulating FSH concentrations. In conclusion, these data provide strong support for the hypothesis that factors can modulate the action of gonadotrophins on follicular cells to augment (IGF-I, inhibin A) or inhibit (TGF alpha/EGF) granulosa and thecal cell differentiation. The challenge for the future in this area of research is to understand how these factors interact to enable one follicle to be selected from an ovulatory cohort.  相似文献   

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