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贵州本地鸡内源生长激素（GH）的测定 总被引：1，自引：0，他引：1
鸡的生长激素（growth hormone,GH）是由脑垂体前叶合成与分泌,其生理功能通过它与生长激素受体（GHR）结合作用产生胰岛素样生长因子-I（IGF-I）等反应来实现,对鸡的生长发育发挥重要的调控作用。从对各种动物进行皮下埋植、注射外源GH等的研究表明：GH对动物具有显著加快肌肉、骨骼生长,促进生长发育,降低饲料报酬的作用。 相似文献
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生长激素(growth hormone,GH)对动物的生长发育具有重要的生理作用.GH与生长激素受体(growth hormone receptor,GHR)结合后才会发挥一系列的生理作用.近年来,人们对GHR结构和功能的研究取得了巨大的进展,并取得了一些重大的突破.现在已清楚了GH-GHR轴激活一些相关的信号转导通路,但并非所有的通路都依赖酪氨酸激酶.作者从以下几个方面总结了GHR作用下的信号转导机制的研究进展:GHR的结构与功能;依赖JAK2的相关信号通路;不依赖JAK2的相关信号通路;GHR信号负调控因子.阐明这些复杂机制,对进一步了解GH对动物不同的生理和病理作用具有重要意义. 相似文献
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1 概述禽类生长的调控机制与哺乳动物相比有许多方面的差异。在哺乳动物 ,例如猪 ,可通过上调肝脏生长激素受体 (GHR) ,提高血液中胰岛素样生长因子 (IGF -I)的水平 ,促进动物生长。而禽类 ,慢性注射生长激素 (GH)并不提高血浆IGF -I水平和动物的生长速度 ,相反却促进脂肪的沉积。此外 ,外周血液中GH水平和垂体GH基因的表达水平与禽类的生长速度并不呈正相关 ,生长速度慢的品种血液GH水平反而高。例如贺淹才等( 2 0 0 0 )通过比较同日龄生长缓慢的泰和鸡和生长速度快的AA肉鸡在早期生长发育过程中血清中GH的水平 ,结果得出 ,在 1… 相似文献
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禽类生长的调控机制与哺乳动物相比有许多方面的差异。在哺乳动物 ,例如猪 ,可通过上调肝脏生长激素受体 (GHR) ,提高血液中胰岛素样生长因子(IGF I)的水平 ,促进动物生长。而禽类 ,慢性注射生长激素 (GH)并不提高血浆IGF I水平和动物的生长速度 ,却促进脂肪的沉积。此外 ,外周血液中GH水平和垂体GH基因的表达水平与禽类的生长速度并不呈正相关 ,生长速度慢的品种血液GH水平反而高。贺淹才等 ( 2 0 0 0 )通过比较同日龄生长缓慢的泰和鸡和生长速度快的AA肉鸡在早期生长发育过程中血清中的GH水平 ,结果在 1日龄和 3 5日龄时 ,泰和… 相似文献
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畜禽生长激素释放因子(GRF)的研究进展 总被引：4，自引：0，他引：4
生长激素释放因子(growth hormone- releasing factor,GRF)又称生长激素释放激素(growth hormone- releasinghorm one,GHRH) ,是存在于脊椎动物体内的一种生物活性多肽,由下丘脑合成并分泌,对脊椎动物的生长、发育及代谢调控起着极其重要的作用。其主要功能是,作为脑垂体生长激素(growth hormone,GH)的正性调控因子,能特异地诱导生长激素的合成与分泌,增高动物机体内的GH水平。而生长激素释放抑制因子(som atostain,SS)则抑制GH的合成与释放。GRF与其伴随的SS低谷诱发形成GH的分泌峰,峰的高度取决于GRF的强度及垂体对GRF的敏感… 相似文献
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生长激素GH是由脑垂体前叶合成和分泌的多肽类激素,是调控整个机体的重要激素,对动物有显著加快肌肉、骨骼生长,降低脂肪含量,促进生长发育及提高饲料报酬的作用。GH在组织和细胞水平发挥其生理作用的第一步是与靶细胞膜表面的生长激素受体(GHR)结合,激活后使两个生长激素受体形成二聚体,从而形成GH(GHR)2复合物(GH分子上有两个GHR结合位点,每一个GH分子能结合两个GHR分子),并激活一系列生化事件,最终产生生物效应。 相似文献
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生长激素与生长激素受体基因的表达 总被引：2，自引：0，他引：2
在动物生长轴中，GH是调控动物生长发育的核心激素，它具有促生长作用。但GH发挥生理作用的第一步是与靶细胞膜表面的GH受体(GHR)结合，由GHR介导将信号传入细胞内从而产生一系列生理效应。在生理激素浓度下，GH 与GHR 以1／2相结合。在超生理激素浓度下，激素饱和了所有的受体分子形成1／1的复合物，阻止了受体二聚化和信息传递。当GH水平提高而GHR基因表达没改善时，不仅GH的作用不能完全发挥，而且可能因为GH过剩而产生负反馈调节，影响其他生理功能。这可能是某些促生长激素轴功能的添加剂在使用一段时间后效果减弱的原因之一。因此，在直接或间接提高GH水平的同时，应该提高GHR基因表达水平，才能最大限度发挥GH的作用。促进GHR基因表达有促进动物生长发育和发展的趋势，可使畜禽生产性能在较高水平的情况下再上新台阶。 相似文献
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半胱胺促生长作用及机理 总被引：4，自引：0，他引：4
在动物的一切代谢活动中,有许多因素参与调节。在内分泌系统对动物生长的调控中,研究较多和较为重要的是生长激素(Growth Hormone,GH),生长激素受生长激素释放激素(growth hor-mone releasing hormone ,GHRH)和生长抑素(So-matostain,SS)的双重控制。GH的释放量取决于这 相似文献
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生长激素受体(growth hormone receptor,GHR)是生长激素(GH)的特定跨膜受体,对动物正常的生长发育具有重要作用。该试验随机选择532只陕北白绒山羊,通过降落PCR (Touch down PCR)方法鉴定陕北白绒山羊GHR基因第一内含子存在的9bp插入缺失(InDel)情况并分析其与体重、生长性状的相关性。研究发现,陕北白绒山羊GHR基因共出现II、ID、DD 3种基因型;相关分析结果表明,在体重、髋宽、体高、荐高和胸深指标上,基因型ID或DD个体相比较II型个体更具显著性优势(P0.05),说明该位点等位基因D更有利于山羊的生长发育。研究表明GHR基因可作为陕北白绒山羊体重和生长性状的候选基因,为陕北白绒山羊产业快速高效发展提供科学理论依据。 相似文献
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生长激素与其靶细胞膜表面的生长激素受体(GHR)结合,可以促进动物生长发育和调节新陈代谢。为获得鸡GHR蛋白,试验通过PCR扩增获得GHR胞外区序列。经双酶切后连接入原核p ET-32a(+)表达载体,构建了鸡GHR胞外结构域的原核表达载体。将该重组质粒转入E. coli BL21(ED3)表达菌株。通过IPTG诱导其表达GHR重组蛋白,并探讨不同IPTG浓度、诱导时间和诱导温度等条件对鸡GHR重组蛋白表达的影响。结果表明:诱导GHR重组蛋白表达的最适条件为IPTG终浓度2.00 mmol/L、诱导时间为4 h、培养温度为37℃,在此条件下,GHR重组蛋白表达量最高。研究结果为后续GHR抗体制备奠定了基础。 相似文献
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B H Breier 《Domestic animal endocrinology》1999,17(2-3):209-218
The somatotropic axis plays a key role in the co-ordination of protein and energy metabolism during postnatal growth. This review discusses the complexity of the regulation of protein and energy metabolism by the somatotropic axis using three main examples: reduced nutrition, growth hormone (GH) treatment and insulin-like growth factor-1 (IGF-1) treatment. Decreased nutrition leads to elevated GH secretion, but it reduces hepatic GH receptor (GHR) number and plasma levels of IGF-1; it also changes the relative concentrations of IGF binding proteins (IGFBPs) in plasma. GH treatment improves the partitioning of nutrients by increasing protein synthesis and decreasing protein degradation and by modifying carbohydrate and lipid metabolism. However, these well-established metabolic responses to GH can change markedly in conditions of reduced nutritional supply or metabolic stress. Short-term infusion of IGF-1 in lambs reduces protein breakdown and increases protein synthesis. However, long-term IGF-1 administration in yearling sheep does not alter body weight gain or carcass composition. The lack of effect of IGF-1 treatment can be explained by activation of feedback mechanisms within the somatotropic axis, which lead to a reduction in GH secretion and hepatic GHR levels. The somatotropic axis has multiple levels of hormone action, with complex feedback and control mechanisms, from gene expression to regulation of mature peptide action. Given that GH has a much wider range of biologic functions than previously recognized, advances in research of the somatotropic axis will improve our understanding of the normal growth process and metabolic disorders. 相似文献
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Polymorphism in promoter region of growth hormone receptor is associated with potential production capacity of insulin‐like growth factor‐1 in pre‐pubertal Holstein heifers 
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下载免费PDF全文 C. Kawashima M. Munakata M. Matsui A. Miyamoto K. Kida T. Shimizu 《Journal of animal physiology and animal nutrition》2016,100(6):1037-1040
Insulin‐like growth factor‐1 (IGF‐1) is one of the important factors for growth, milk production and reproductive functions and mainly released from the liver in response to growth hormone (GH) via GH receptor (GHR) in cattle. Recently, some single nucleotide polymorphisms (SNPs) were identified in the bovine GHR gene. Some GHR‐SNPs were shown to be related to plasma IGF‐1 concentration in cattle. Hence, the capacity to IGF‐1 production in the liver might be affected by GHR‐SNP and associated with performance in the future. This study examined whether GHR‐SNP is associated with IGF‐1 production in the liver of pre‐pubertal heifers. In 71 Holstein calves, blood samples for genomic DNA extraction were obtained immediately after birth. To genotype the GHR‐SNPs in the promoter region, polymerase chain reaction (PCR) products were digested with restriction enzyme NsiI (cutting sites: AA, AG and GG). All heifers at 4 months of age were intramuscularly injected with 0.4 mg oestradiol benzoate. Blood samples were obtained from the jugular vein just before (0 h) and 24 h after injection. The number of AA, AG and GG at the NsiI site was 0, 17 and 54 respectively. In AG and GG, plasma GH concentrations were higher pre‐injection than 24 h post‐injection (p < 0.01). Moreover, plasma GH concentrations in AG post‐injection were higher than in GG (p < 0.05). In contrast, the GG genotype exhibited higher plasma IGF‐1 concentrations in pre‐injection than post‐injection (p < 0.01), although oestradiol did not change IGF‐1 concentration in the AG genotype. We conclude that the GG polymorphism in the promoter region of GHR is associated with a higher potential capacity of IGF‐1 production in the liver of cattle. 相似文献
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Pawłowski KM Popielarz D Szyszko K Gajewska M Motyl T Król M 《Veterinary and comparative oncology》2012,10(1):2-15
Canine mammary gland has been identified as a major site of the extrapituitary growth hormone (GH) production. This finding is linked to its role in tumourigenesis of the mammary gland. Our previous studies indicated the role of GH and GH receptor (GHR) in regulation of proliferation and apoptosis. Thus, we have optimized the ghr RNA interference method in canine mammary carcinoma cell line CMT-U27. We have analysed the effect of GHR reduction on the intracellular signalling and the cell cycle and apoptosis. The results showed that GHR reduction decreased the p-ERK1/2 expression and caused increase of apoptosis and decrease in number of cells at S and G2M phases. This study indicates that GHR besides proliferative effect promotes growth by increasing cell survival. It can tilt the balance between proliferation and death in cancer cells. 相似文献
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The growth hormone receptor (GHR) is the key regulator of postnatal growth which belongs to the type Ⅰ cytokine receptor that mediates many functions regulated by growth hormone (GH). Monoclonal antibodies (mAb) to the GHR have been important tools for the study of this receptor. All these anti-GHR mAbs, designated 1H2, 1A9, 2C3 and mAb263, are highly reactive with GHR, but 1A9 does not promote growth in hypophysectomized rats, 2C3 can do and this effect will be inhibited in the presence of GH. mAb263 as the commercial monoclonal antibody that binding to the receptor has a similar effect with GH, not only can recognise GHR,but also can induce a conformational change of the receptor in a similar manner, but not identical with GH. 相似文献
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Mondal M Rajkhowa C Prakash BS 《Journal of animal physiology and animal nutrition》2007,91(1-2):68-73
The role of growth hormone (GH) in postnatal somatic growth is well established. Its basal level and relation to growth performance in different age group mithun (Bos frontalis), a semiwild ruminant has not been characterized until now. To estimate the normal blood GH level and also to assess the influence of age and body weight (BW) on blood GH level in captive mithuns, a total of 65 female mithuns was divided into six age groups (group I, 0-6 months; group II, >6-12 months; group III, >1-2 years; group IV, >2-2.5 years; group V, >2.5-3.0 years and group VI, >3.0 years). Blood samples collected weekly for six consecutive weeks were assayed for GH. GH was also estimated in the samples collected from six growing mithuns at -60, -45, -30, -15, -10, -5 and 0 min prior to GH-releasing hormone (GHRH) administration for calculation of basal GH level and at 5, 10, 15, 30 min and thereafter at 15-min interval up to 8 h post-GHRH to assess blood GH response following GHRH administration in growing mithuns. For calculation of basal plasma GH in adult mithuns, GH was measured in blood samples collected at 30-min interval for 24 h from four animals. BW of all animals was recorded on two consecutive days per week and average of weekly BW was considered for growth rate calculation. It was found that both mean GH and GH per 100 kg BW between the age groups differ (p < 0.01). With increasing age and BW, GH and GH per 100 kg BW both decreased (p < 0.01). The age group with higher plasma GH and GH per 100 kg BW showed higher growth rates (r = 0.83 and 0.97 respectively). Interestingly, mean plasma GH for six consecutive weeks in all the groups showed much greater GH concentration (group I, 86.6 +/- 9.7 ng/ml to group VI 33.2 +/- 5 ng/ml) than reported in other species. Mean basal plasma GH calculated in growing and adult mithuns was 29.6 +/- 4.01 ng/ml and around 25 +/- 3.6 ng/ml respectively. The GH peak (444 +/- 21.3 ng/ml) was registered at 15 min post-GHRH administration in growing mithuns. In conclusion, age and BW influence plasma GH and GH per 100 kg BW but the latter is a better indicator of growth. The basal plasma GH and GH response to GHRH administration is six to eight and four to five times higher in mithun than in other species reported so far. An accurate assessment of the relationship between GH profiles and protein metabolism, proper receptor level study for GH action at the cellular level and the interaction of GH with other growth factors awaits better understanding of higher GH in this unique species. 相似文献
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Blum JW Elsasser TH Greger DL Wittenberg S de Vries F Distl O 《Domestic animal endocrinology》2007,33(3):245-268
Perturbations in endocrine functions can impact normal growth. Endocrine traits were studied in three dwarf calves exhibiting retarded but proportionate growth and four phenotypically normal half-siblings, sired by the same bull, and four unrelated control calves. Plasma 3,5,3'-triiodothyronine and thyroxine concentrations in dwarfs and half-siblings were in the physiological range and responded normally to injected thyroid-releasing hormone. Plasma glucagon concentrations were different (dwarfs, controls>half-siblings; P<0.05). Plasma growth hormone (GH), insulin-like growth factor-1 (IGF-1) and insulin concentrations in the three groups during an 8-h period were similar, but integrated GH concentrations (areas under concentration curves) were different (dwarfs>controls, P<0.02; half-siblings>controls, P=0.08). Responses of GH to xylazine and to a GH-releasing-factor analogue were similar in dwarfs and half-siblings. Relative gene expression of IGF-1, IGF-2, GH receptor (GHR), insulin receptor, IGF-1 type-1 and -2 receptors (IGF-1R, IGF-2R), and IGF binding proteins were measured in liver and anconeus muscle. GHR mRNA levels were different in liver (dwarfs相似文献
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IGF-Ⅰ能够促进细胞的增殖分化和代谢过程,而其表达是受STAT介导的,该通路最终受到生长激素(GH)的调控。生长激素与生长激素受体结合激活JAK家族,使得STAT家族成员,特别是STAT5磷酸化。磷酸化的STAT5进入细胞核内,与IGF-Ⅰ基因上的STAT5结合位点结合,激活胰岛素样生长因子-Ⅰ(IGF-Ⅰ)的表达,IGF-Ⅰ再通过血液循环到达机体的局部组织,促进组织细胞的生长和分化。作者对动物生长轴中STAT和IGF-Ⅰ的组成、功能以及STAT调控IGF-Ⅰ表达的分子机理的研究进展作一综述。 相似文献