超强激素

超强激素董为人李进李福山（第一军医大学细胞生物学实验室,广州５１０５１５）关键词超强激素糖蛋白激素糖蛋白激素为一组进化保守的激素,参与生殖和代谢调节,广泛存在于种属间,如鳗鱼和人类。该类激素的家族包括垂体腺分泌的促性腺激素,如促卵泡素（ＦＳＨ）、黄体...     

促黄体素β基因表达中的转导通路及转录因子

促性腺激素释放激素 (GnRH)为下丘脑促垂体激素 ,其脉冲式地释放调节垂体促卵泡素(FSH)和促黄体素 (LH)的合成与释放 ,进而调节动物的生殖活动。LH是由α亚基和 β亚基组成的异二聚体糖蛋白激素 ,其中 β亚基决定激素的特异性。LHβ基因的表达是由GnRH诱发的 ,此过程主要依靠PKC和Ca2 两类信号通路 ,并调节LHβ基因的表达。目前已经发现 ,多种转录因子 ,如早期生长反应基因 (Egr 1)、核受体SF 1基因、Ptx1基因和Sp1基因等 ,通过与LHβ亚基基因的启动子区直接结合 ,而对该基因的表达进行调控。     

亚胺环己酮可模拟抑素对垂体促性腺激素的调控作用

抑素(inhibin)是由卵巢颗粒细胞或睾丸支持细胞分泌的一种糖蛋白激素,它对垂体促性腺激素具有负反馈调节作用,亚胺环己酮(cycloheximide)是一种蛋白质生物合成的强抑制剂。为了研究抑素的作用机制,作者比较了抑素(32KDa,从猪卵泡液提取)和亚胺环己酮分别对离体培养的大鼠腺垂体细胞合成与分泌促性腺激素的作用,结果表明:(1)抑素和亚胺环己酮都能抑制腺垂体卵泡刺激素(FSH)的基础分泌及细胞内 FSH 含量(ED_(50)分别为1.0ng/ml 和22.5ng/ml),但它们都不改变黄体生成素(LH)的基础分泌及细胞     

根田鼠下丘脑促性腺激素释放激素的放射免疫学测定

利用大鼠促性腺激素释放激素放射免疫学测定试剂检测了根田鼠下丘脑促性腺激素释放激素水平．测定线性范围为2.5 Pg至160pg/管,批内和批间差为1.7％ (n=10)和7.8%（n=4),样品平均标准回收率为108.2±8.4％。根田鼠下丘脑促性腺激素释放激素测定为0.28±0.04 ng/mg湿重组织。从根田鼠下丘脑提取物稀释曲线与大鼠(人工合成)促性腺激素释放激素有较好的平行关系判断, 可以推知根田鼠下丘脑促性腺激素释放激素结构活性类似于大鼠(人工合成)的活性。     

PROP1与联合垂体激素缺乏症

垂体特异性转录因子祖先蛋白(PROP l),是成对同源转录因子,在垂体腺中呈特异性表达,参与早期胚胎垂体的发育,因此,PROP1基因对于垂体前叶的发育是必需的。PROP1启动胚胎期垂体特异性转录因子(PIT-1)的起始表达并维持个体出生后的持续表达,且可直接促使PIT-1细胞系的前体分化为促性腺细胞系。其基因突变可使人、鼠患有联合垂体激素缺乏症(CPHD),表现为生长激素(GH)、促乳素(PRL)、促甲状腺素(TSH)以及促黄体激素(LH)、促卵泡激素(FSH)或促肾上腺皮质激素(ACTH)缺乏,垂体核磁共振成像显示垂体萎缩。在其它哺乳动物中PROP1突变也会引起垂体和性腺激素异常。就PROP1基因的结构与功能,以及与CPHD间的关系作一综述。     

Con．A-Sepharose亲和吸附剂的制备及其纯化某些蛋白质的性能

伴刀豆球蛋白A (Con.A) 与溴化氰活化的琼脂糖(Sepharose)偶联制成的Con.A-Sepharose亲和吸附剂具有纯化某些糖蛋白一类物质的性能。因此,人血清中的胰蛋白酶抑制剂,碱性磷酸酯酶,小牛脾磷酸二酯酶,不同变种的甲胎球蛋白和某些激素如绒毛膜促性腺激素(HCG),促黄体激素(LH)等物质都可用它纯化。此法操作简单、样品回收率较高,故它已成为纯化上述一类物质的有效工具。我们参考Steven的方法,用自己制备的     

鲫鱼籽唾液酸糖蛋白的N-糖链结构及生物活性

鲫鱼是常规食用淡水鱼,其鱼籽含有大量唾液酸化糖蛋白。对鲫鱼籽糖蛋白进行纯化,研究其N-糖链结构和生物活性。结果发现:鲫鱼籽糖蛋白分子量主要分布在19.7×10~4、2.7×10~4和2.2×10~4左右。利用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)解析主要糖蛋白上N-糖链,发现其N-糖链结构主要为双天线型或三天线型分叉结构,末端唾液酸结合在半乳糖或N-乙酰氨基-半乳糖上。生物活性分析表明,鲫鱼籽糖蛋白具有阻止磷酸钙沉淀能力和一定清除DPPH自由基能力,对HaCat细胞具有促生长能力,并具有较强的促凝血活性。     

促性腺激素释放激素受体的结构及其生物学功能

促性腺激素释放激素受体(GnRHR)属于类视紫红质G-蛋白结合受体(GPCRs)家族的成员.当促性腺激素释放激素(GnRH)与GnRHR结合后,一系列细胞内信号通路被激活从而调节和表达各种生物学功能.本文对GnRHR的基因结构、分子结构、信号调节及生物学功能等进行了综述.     

人抑制素的分子结构及其生物学特性

抑制素是性腺产生的一种糖蛋白激素,由双硫键联结的两个不同的亚单位(即α和β肽链)组成,抑制垂体促性腺激素(尤其是FSH)的产生和分泌。近年来,国外许多学者十分关注抑制素在人类生殖生理活动的重要地位,并为寻找特异性干扰精子发生和滤泡生长的节育途径,探索不育症的机理而进行深入的研究。本文简要综述人抑制素的分子结构及其生物学特性。     

鸡FSH β基因5’调控区单核苷酸多态性分析

促卵泡激素(follicle-stimulating hormone, FSH)是由垂体前叶分泌的糖蛋白类促性腺激素.运用PCR-SSCP法检测鸡FSH β基因5'调控区的单核苷酸多态性.检测发现该区域存在6个SNP位点,即G-494A,T-470A,A-464G,-450处插入碱基A,A-405G,A-361G.同时分析了SNPs与文昌鸡早期产蛋性能的相关性.结果显示,FSH β基因调控区SNPs位点与鸡的早期产蛋性能显著相关.     

真菌激素研究进展

真菌种类繁多,与人类健康、工农业生产和生态系统物质循环的关系非常密切。真菌合成多种性激素、植物激素和动物激素,这些内源激素以及来自动植物产生的外源激素能够被真菌感知,并影响真菌的生长发育、子实体形成、代谢、致病性和共生性等。然而,对真菌激素的合成和信号转导途径,及其起源和进化还知之不多。建立真菌激素学将极大地促进对真菌激素的研究和应用。     

The gastrointestinal endocrine system

Gastrointestinal endocrinology is the study of the hormonal regulation of digestion. A number of characterized polypeptide hormones have been localized in specific gastroenteropancreatic endocrine cells. The fact that some of these hormones are also found in nerve and brain cells has given rise to the concept of a gut-brain axis. The functional capacities of these endocrine cells are determined by their anatomic location; the luminal exposure of gastroenteric endocrine cells represents an additional avenue for stimulation and release that is not open to pancreatic endocrine cells. Gastroenteropancreatic hormones regulate carbohydrate metabolism, gastric acid secretion, pancreatic exocrine and gallbladder function, gastrointestinal motility and blood flow. These important regulatory hormones may in turn be controlled by a series of gastroduodenal releasing hormones.Diabetes mellitus is the most important metabolic disorder related to a gastroenteropancreatic hormone imbalance. Most tumours producing these hormones are of pancreatic origin and produce a number of hormones; insulinomas and gastrinomas are detected readily because of the serious metabolic distrubances they cause. Other instances of altered circulating concentrations of these hormones result from rather than cause the disease.The challenge of future study is to determine if postprandial changes in the plasma concentrations of these hormones are sufficient or necessary, or both, for the control of digestion.     

The hormonal system of the unicellular Tetrahymena: a review with evolutionary aspects

The unicellular ciliate, Tetrahymena has receptors for hormones of the higher ranked animals, these hormones (e.g. insulin, triiodothyronine, ACTH, histamine, etc.) are also produced by it and it has signal pathways and second messengers for signal transmission. These components are chemically and functionally very similar to that of mammalian ones. The exogenously given hormones regulate different functions, as movement, phagocytosis, chemotaxis, cell growth, secretion, excretion and the cells' own hormone production. The receptors are extremely sensitive, certain hormones are sensed (and response is provoked) at 10-21 M concentration, which makes likely that the function could work by the effect of hormones produced by the Tetrahymena itself. The signal reception is selective, it can differentiate between closely related hormones. The review is listing the hormones produced by the Tetrahymena, the receptors which can receive signals and the signal pathways and second messengers as well, as the known effects of mammalian hormones to the life functions of Tetrahymena. The possible and justified role of hormonal system in the Tetrahymena as a single cell and inside the Tetrahymena population, as a community is discussed. The unicellular hormonal system and mammalian endocrine system are compared and evolutionary conclusions are drawn.     

Interactions between nitric oxide and plant hormones in aluminum tolerance

Nitric oxide (NO) is involved, together with plant hormones, in the adaptation to Al stress in plants. However, the mechanism by which NO and plant hormones interplay to improve Al tolerance are still unclear. We have recently shown that patterns of plant hormones alteration differ between rye and wheat under Al stress. NO may enhance Al tolerance by regulating hormonal equilibrium in plants, as a regulator of plant hormones signaling. In this paper, some unsolved issues are discussed based on recent studies and the complex network of NO and plant hormones in inducing Al tolerance of plants are proposed.     

Clinical significance and perspectives of gastrointestinal peptide hormones.

Present knowledge about gastrointestinal peptide hormones is discussed from three points of view: (a) diagnostic significance of these hormones; (b) states characterized by over-production or deficiency of peptide hormones; (c) clinical application and perspectives of gastrointestinal hormones. The data in the literature are subjected to a critical analysis; in addition, the author's own experiments are discussed.     

Developing a model of plant hormone interactions

Plant growth and development is influenced by mutual interactions among plant hormones. The five classical plant hormones are auxins, cytokinins, gibberellins, abscisic acid and ethylene. They are small diffusible molecules that easily penetrate between cells. In addition, newer classes of plant hormones have been identified such as brassinosteroids, jasmonic acid, salicylic acid and various small proteins or peptides. These hormones also play important roles in the regulation of plant growth and development. This review begins with a brief summary of the current findings on plant hormones. Based on this knowledge, a conceptual model about interactions among plant hormones is built so as to link and develop an understanding of the diverse functions of different plant hormones as a whole in plants.Key words: abscisic acid, auxin, brassinosteroids, cytokinins, ethylene, gibberellins, jasmonic acid, salicylic acid, plant peptide hormones     

Invertebrate neuropeptide hormones

The development of a long-term research program on the neurosecretory hormones of arthropods is described. The purification and full characterization of the first invertebrate neurohormones, the red pigment-concentrating hormone (RPCH) and the distal retinal pigment hormone (DRPH) demonstrated that they are peptides, an octapeptide and an octadecapeptide, respectively. Physiological function studies with the pure hormones and their synthetic preparations showed that the RPCH acts as a general pigment-concentrating hormone (PCH), and that the DRPH, in addition to its light-adaptive function, also constitutes a general pigment-dispersing hormone (PDH). In the regulation of the color-adaptation of the animals, the two hormones act as antagonists. The chromatophorotropic activities are widely distributed within the arthropod neuroendocrine systems. Purification of the pigment-concentrating activities from the locust corpora cardiaca lead to the isolation and characterization of the first insect neurohormones, the adipokinetic hormones (AKH I and AKH II). These two hormones, AKH I being a decapeptide and AKH II being an octapeptide, are close structural analogs to the crustacean PCH, demonstrating a common evolution of arthropod neurohormones. The hormones of this PCH-family all cross-react, but structure-function studies of the hormones show that quite different parts of their structure are involved in their binding to the various receptors.     

Human skin: an independent peripheral endocrine organ

The historical picture of the endocrine system as a set of discrete hormone-producing organs has been substituted by organs regarded as organized communities in which the cells emit, receive and coordinate molecular signals from established endocrine organs, other distant sources, their neighbors, and themselves. In this wide sense, the human skin and its tissues are targets as well as producers of hormones. Although the role of hormones in the development of human skin and its capacity to produce and release hormones are well established, little attention has been drawn to the ability of human skin to fulfil the requirements of a classic endocrine organ. Indeed, human skin cells produce insulin-like growth factors and -binding proteins, propiomelanocortin derivatives, catecholamines, steroid hormones and vitamin D from cholesterol, retinoids from diet carotenoids, and eicosanoids from fatty acids. Hormones exert their biological effects on the skin through interaction with high-affinity receptors, such as receptors for peptide hormones, neurotransmitters, steroid hormones and thyroid hormones. In addition, the human skin is able to metabolize hormones and to activate and inactivate them. These steps are overtaken in most cases by different skin cell populations in a coordinated way indicating the endocrine autonomy of the skin. Characteristic examples are the metabolic pathways of the corticotropin-releasing hormone/propiomelanocortin axis, steroidogenesis, vitamin D, and retinoids. Hormones exhibit a wide range of biological activities on the skin, with major effects caused by growth hormone/insulin-like growth factor-1, neuropeptides, sex steroids, glucocorticoids, retinoids, vitamin D, peroxisome proliferator-activated receptor ligands, and eicosanoids. At last, human skin produces hormones which are released in the circulation and are important for functions of the entire organism, such as sex hormones, especially in aged individuals, and insulin-like growth factor-binding proteins. Therefore, the human skin fulfils all requirements for being the largest, independent peripheral endocrine organ.     

Hormones of youth?

Ageing is doubtless complicated, lifelong process regarding many body systems, including endocrine system. Human hormonal system changes with age. Although these changes concern secretion of many hormones, they are not unidirectional, there are hormones secretion of which is diminished, whereas secretion of the others is augmented or not changed with age. A possible role of hormones which are often termed "hormones of youth"(growth hormone, melatonin, and dehydroepiandrosterone) in the ageing process is discussed in the present article. Although some experimental and clinical data indicate that these hormones may play some role in the human ageing process, it appears from presented data that we are still far away from conclusion that, indeed, one (or more) of the discussed hormones could be considered as "hormone of youth", which may slow down ageing process. However, some symptoms of the quality of life improvement following administration of dehydroepiandrosterone, melatonin, and growth hormone may suggest that they may promote so called "successful aging".     

Recent advances in the hormonal treatment of sterility (author's transl)]

The present trends in the utilization of hormones in the treatment of sterility are reviewed, special reference being made to the utilization of gonadotrophins, hypothalamic hormones and gonadal hormones as well as other substances (clomiphene, epimestrol, cyclophenyl) that are also utilized in this type of treatments.