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1.
生长激素(GH)是调节动物生长和发育的重要激素之一。最近的许多研究表明,GH与动物的生殖也悉悉相关。GH可促进卵泡生长,加快卵母细胞成熟,协助排卵,加快初情期与性成熟,促进生殖器官的生长与发育,刺激胎盘生长,促进胚胎的生长与分化,还对生殖激素有调节作用。由此可见,GH在生殖上的作用相当广泛,是动物生殖的一个重要调节激素。  相似文献   

2.
生长激素(GH)是调节动物生长和发育的重要激素之一。最近研究表明,GH也能调节类固醇的生成、配子的形成、性腺分化以及促性腺激素的分泌和应答,GH在繁殖上具有重要的作用。而且,其他一些组织,如性腺、胎盘和乳房组织中也能生成GH,并且以自分泌或旁分泌方式调节由垂体GH直接调节的一些过程。  相似文献   

3.
生长激素(GH)是调节动物生长和发育的重要激素之一。最近研究表明,GH也能调节类固醇的生成、配子的形成、性腺分化以及促性腺激素的分泌和应答,GH在繁殖上具有重要的作用。而且.其他一些组织,如性腺、胎盘和乳房组织中也能生成GH.并且以自分泌或旁分泌方式调节由垂体GH直接调节的一些过程。  相似文献   

4.
半胱胺在畜牧生产中的应用   总被引:4,自引:0,他引:4  
动物的生长受到多种激素的调节,生长激素、甲状腺激素(T3、T4)、胰岛素和性激素均对动物生长起着重要的作用,但起核心作用的激素是生长激素(GH)。在动物体内生长激素的生成、释放受到下丘脑生长激素释放因子(GHRF)和生长抑素(SS)的双重调节,GHRF促进GH的分泌,SS抑制GH的分泌。研究表明,半胱胺(Cysteamine,CS)能够有效降低生长抑素的活性,提高生长激素、胰岛素、甲状腺激素等激素的含量,促进畜禽的生长,在畜牧生产中具有良好的应用前景。  相似文献   

5.
动物生长是个复杂的代谢过程,受基因、激素、营养、环境等多方面的影响,这些因素直接或间接作用内分泌系统而实现对生长的影响。生长激素(GH)是由脑垂体分泌的激素,主要作用是促进RNA的合成,使器官得到生长和发育。动物的生长是由下丘脑一垂体一生长激素调节系统来调节。下丘脑分泌的生长激素释放因子(GRF)和生长素抑制激素(SS)属于高位调节因子,他们可以调节动物体内激素的整体水平,  相似文献   

6.
通过免疫技术调控动物生长和胴体品质   总被引:3,自引:0,他引:3  
1 生长激素的免疫调控 生长激素(GH)是一种重要的促进生长和调节代谢的激素。免疫调控技术通过瞄准生长激素轴,主要以三种方式达到提高生长速度,改善胴体品质的目的。这三种方式是促进生长激素分泌、提高生长激素活性、模拟生长激素的作用。 1.1 免疫中和环状脑肠肽及促进内源GH的分泌 生长激素的分泌,受多种因素影响,其中生长抑素(SS)和生长激素释放因子(GRF)是两种最主要的影响因子。SS抑制GH的分泌,而GRF促进GH的分泌。因此通过免疫中和SS,能提高机体内源性GH的分泌,从而促进动物生长。  相似文献   

7.
垂体分泌的生长激素 (GH)是调节整个机体生长代谢的一种多功能激素。关于GH分泌调节的研究一直是营养学界研究的热点。最近在生长激素促释放素 (growthhormonesecretagogues,GHSs)对GH分泌调节的研究过程中发现的活性肽ghrelin对GH、胃酸的分泌 ,采食量的调节等方面起重要作用 ,本文将综述有关ghrelin的最新研究进展  相似文献   

8.
生长激素是调节动物生长的众多激素中最重要的一种。调控动物生长激素分泌释放是调控动物生长的重要方式。本文综述了目前存在的运用生物技术调控动物生长激素分泌释放的方法 ,包括 :注射外源生长激素、注射外源生长激素释放因子、生长抑素免疫、转GH GRF基因动物以及GRF基因直接转移 ,并指出GRF基因直接转移是最有前途的调控动物生长激素分泌释放的方法。  相似文献   

9.
卵泡发育是一个周期性的过程,受多种激素的调控。其中,抗苗勒管素(AMH)主要来源于人和动物的腔前卵泡和小腔卵泡的颗粒细胞,在卵巢原始卵泡募集和优势卵泡选择中起重要作用。研究证明,AMH参与卵泡发育的调节,可用于预测超排反应和选择供体动物。探讨AMH生理学功能对动物繁殖性能的影响,为AMH的临床应用提供理论依据。  相似文献   

10.
动物生长轴的激素调控   总被引:6,自引:0,他引:6  
1 生长轴动物生长是一个复杂的生物代谢过程 ,受基因型、激素、营养、环境等多方面的影响。这些因素对生长的影响作用都是通过直接或间接影响动物内分泌系统来实现的。人和动物的生长是由促生长激素轴来调控的 ,促生长激素轴由生长激素释放因子 (GRF)、生长激素 (GH)和胰岛素样生长因子 (IGF)构成 ,其中生长激素是调控整个机体生长的最重要的激素。生长轴是动物体内从下丘脑———垂体———靶器官的一系列激素及其受体所组成的神经内分泌系统 ,如图 1所示。注 :GRF :生长激素释放因子 SS :生长抑制激素  GH :生长激素 IGF :胰…  相似文献   

11.
卵泡从原始卵泡发育为成熟卵泡,直至排卵、黄体发育等过程都受到精密的调控,产生大量的优势卵泡是绵羊产多羔及实现快速扩繁的关键因素。研究发现,相关信号通路和转录因子通过影响绵羊卵泡中卵母细胞、颗粒细胞的生长,进而调控卵泡的发育成熟,对这些信号通路进行深入了解,有助于探索卵泡发育的调控机制,早日实现绵羊高效繁育。Notch是卵泡发育过程中发挥重要作用的高度保守信号通路,PI3K/AKT/mTOR信号通路各成员都是广泛存在于细胞内的信号转导分子,在卵泡发育早期发挥了主要作用,还有间隙连接(gap junction,GJ)和跨带突触(transzonal projections,TZPs)等物理连接方式,在细胞间的交流通讯起到重要作用。作者详细介绍了Notch信号通路、PI3K/AKT/mTOR信号通路、间隙连接及跨带突触的结构功能在绵羊卵泡发育中的调控作用,为进一步探明绵羊卵泡发育的调控机制提供参考。  相似文献   

12.
生长激素基因多态性与生产性能关系的最新研究   总被引:5,自引:3,他引:5  
生长激素是一种具有广泛生理功能的蛋白肽激素,尤其对动物的生长发育具有重要作用。研究GH基因功能区的突变对其蛋白功能的影响,以及对哺乳动物生长发育的影响,具有重要的理论意义和实践意义。因此在生产中探讨GH基因多态性与生产性能的关系,从而达到提高动物生产水平的目的,成为人们关注的重要课题。  相似文献   

13.
毛囊发育与周期性生长的调控信号通路研究进展   总被引:1,自引:0,他引:1  
毛囊是皮肤的重要附属结构,也是控制哺乳动物被毛生长的重要器官。哺乳动物出生后,毛囊具有终生呈周期性生长的特性,毛囊干细胞、毛乳头细胞、毛母质细胞及脂肪细胞等参与了毛囊周期性生长,Wnt、BMP、Notch等信号通路与毛囊生长发育密切相关。本文从哺乳动物毛囊的结构、周期性生长特征以及参与毛囊周期性生长调控的相关信号通路等进行了详细阐述,为深入了解哺乳动物毛囊的周期性生长调控机制,以及为今后指导绒山羊、绵羊、长毛兔等毛用动物和獭兔、水貂、狐狸、貉等皮用动物选育和提高生产性能提供理论参考。  相似文献   

14.
Recent data on the association between growth hormone (GH) and male and female reproductive processes, as well as the effects of GH on these processes and on some reproductive and non-reproductive disorders, and possible extra- and intracellular mediators of its action are reviewed. The available data suggest that GH is an important endocrine and autocrine/paracrine regulator of reproduction. It controls proliferation, apoptosis, growth and differentiation and the secretory and generative activities of different reproductive organs. It also regulates their response to gonadotrophin-releasing hormone (GnRH) and gonadotropins. Despite the effects of GH on the IGF/IGFBP (insulin-like growth factor binding protein) system, oxytocin, steroids, activin, gonadotropin and gonadotropin receptors, the majority of GH's actions on the reproductive processes are probably mediated not by these substances but by specific GH receptors acting through cAMP/protein kinase A, protein kinase G, tyrosine kinase-, MAP kinase and CDC2 kinase-dependent intracellular mechanisms. Although GH treatments can increase the risk of some reproductive and non-reproductive disorders, they may be useful in improving gonadal function, inducing superovulation and in embryo production.  相似文献   

15.
应用免疫组化方法结合计算机图像分析技术,分析同期发情后0、5、9、12、15d的绵羊卵巢中血管内皮生长因子(Vascular endothelial growth factor,VEGF)表达强度变化,以期了解VEGF在绵羊卵巢发情周期不同时期的表达规律。结果显示:VEGF阳性目标主要出现于卵泡膜与颗粒细胞。原始卵泡、初级卵泡、次级卵泡VEGF表达依次增强(P〈0.05)。发情周期0~5d,大窦腔卵泡(颗粒细胞4~8层)VEGF表达量骤然上升(P〈0.05),而9d开始显著下降,与5d比较差异显著(P〈0.05)。12d继续下降(P〈0.05)且为最低值,15d又明显上升(P〈0.05)。VEGF在卵巢间质呈弱表达,各个时期之间差异不显著(P〉0.05)。结果表明,绵羊卵巢存在着血管周期性新生的变化特点,而VEGF在这种周期性血管新生过程中起着重要的调控作用。  相似文献   

16.
营养不仅是畜禽的生长发育和繁殖的物质基础,而且对于维持机体免疫系统具有重要作用.免疫应激影响畜禽的生产性能和免疫功能,本文阐述了营养对畜禽免疫应激的重要作用.  相似文献   

17.
Kisspeptin(Kp) is synthesized in the arcuate nucleus and preoptic area of the hypothalamus and is a regulator of gonadotropin releasing hormone in the hypothalamus.In addition,Kp may regulate additional functions such as increased neuropeptide Y gene expression and reduced proopiomelanocortin(POMC) gene expression in sheep.Other studies have found a role for Kp to release growth hormone(GH),prolactin and luteinizing hormone(LH)from cattle,rat and monkey pituitary cells.Intravenous injection of Kp stimulated release LH,GH,prolactin and follicle stimulating hormone in some experiments in cattle and sheep,but other studies have failed to find an effect of peripheral injection of Kp on GH release.Recent studies indicate that Kp can stimulate GH release after intracerebroventricular injection in sheep at doses that do not release GH after intravenous injection.These studies suggest that Kp may have a role in regulation of both reproduction and metabolism in sheep.Since GH plays a role in luteal development,it is tempting to speculate that the ability of Kp to release GH and LH is related to normal control of reproduction.  相似文献   

18.
猪腔前卵泡体外培养研究进展   总被引:1,自引:1,他引:0  
哺乳动物卵巢中有数量丰富的腔前卵泡,腔前卵泡体外发育的研究,对于揭示卵子发生和卵泡发育的内在规律有重要意义,并可以最大限度利用卵巢资源促进动物繁殖,保护濒临灭绝物种及人类生殖健康。猪腔前卵泡自开始研究以来,已取得了很大的进展。作者简要阐述了猪腔前卵泡培养方法、培养条件的研究进展及其体外培养技术存在的问题和发展前景。  相似文献   

19.
The aim of the study and short review was to present evidence that growth hormone (GH), locally produced insulin-like growth factors (IGFs), and IGF-binding proteins (IGFBPs) may have an important role in the control of ovarian function. There is clear evidence for a distinct GH-receptor mRNA expression and protein production in follicles (oocytes and granulosa-cumulus cells) and corpus luteum (CL). In hypophysectomized ewes, GH and LH are necessary for normal CL development. IGF-1 mRNA in the follicles is expressed in theca interstitial cells (TIC) and granulosa cells (GC) with already higher levels in the TIC before follicle selection. In contrast, IGF-2 is mainly expressed in the TIC. The IGFR-1 mRNA is expressed in both the TIC and GC, with increasing levels in GC during the final development of dominant follicles. IGF-1 is a very potent stimulator of progesterone and oxytocin release in GC. IGFBP-1, -2, -3, -4, -5, and -6 have been isolated from follicular fluid or ovarian tissue. Studies indicate that IGFBP expression and production in the developing follicle is dependent on both cell type and follicle size and is regulated by IGF-1 and gonadotropins. The highest expression of IGF-1 and IGFR-1 mRNA was demonstrated during the early luteal phase. Distinct receptors for IGF-1 and IGF-2 were present in CL membrane preparations at all stages investigated. Intense immunostaining for IGF-1 was observed mainly in bovine large and small luteal cells and in a limited number of endothelial cells. In contrast, IGF-2 protein was localized in perivascular fibroblast and pericytes of the capillaries. With the use of a microdialysis system, we found that in vitro and in vivo IGF-1, IGF-2, and GH stimulated the release of progesterone in cultures of luteal cells or intact tissues. In conclusion, there is clear evidence for a central role of the IGFs, IGFBPs, and GH in follicular development and CL function.  相似文献   

20.
Kisspeptin (Kp) is synthesized in the arcuate nucleus and preoptic area of the hypothalamus and is a regulator of gonadotropin releasing hormone in the hypothalamus. In addition, Kp may regulate additional functions such as increased neuropeptide Y gene expression and reduced proopiomelanocortin (POMC) gene expression in sheep. Other studies have found a role for Kp to release growth hormone (GH), prolactin and luteinizing hormone (LH) from cattle, rat and monkey pituitary cells. Intravenous injection of Kp stimulated release LH, GH, prolactin and follicle stimulating hormone in some experiments in cattle and sheep, but other studies have failed to find an effect of peripheral injection of Kp on GH release. Recent studies indicate that Kp can stimulate GH release after intracerebroventricular injection in sheep at doses that do not release GH after intravenous injection. These studies suggest that Kp may have a role in regulation of both reproduction and metabolism in sheep. Since GH plays a role in luteal development, it is tempting to speculate that the ability of Kp to release GH and LH is related to normal control of reproduction.  相似文献   

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