首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
采用放射配体受体结合分析的方法,研究了小鼠大脑皮层、小脑、海马、下丘脑四个脑区和卵巢、子宫中孕酮对外源性[3H]-GABA与GABAA受体结合的影响,结果表明:1)孕酮使中枢四个脑区和子宫中外源性[3H]-GABA的结合量显著下降;2)GABAA受体拮抗剂Picro-toxin与孕酮+Picrotoxin对[3H]-GABA结合的影响无明显差别;3)在卵巢中孕酮对[3H]-GABA与GABAA受体的结合无明显影响。这表明中枢和子宫存在的孕酮,能降低GABAA受体对外源性[3H]-GABA的结合,而且可被Picrotoxin所拮抗,提示孕酮可能通过影响GABAA的功能,发挥巴比妥样效应,并且其作用位点可能与Picrotoxin的位点靠近。  相似文献   

2.
白蚁作为具有品级多型和精致行为的高度社会化昆虫,品级分化是白蚁社会化生活的基础,也是生命科学的重要议题。从品级分化的类型及其影响因子、个体识别、信息传递、激素调控机理等方面,对白蚁品级分化的研究现状进行综述,为白蚁群体结构的深入理解及有效防治提供参考。白蚁品级分化主要分为生殖个体分化和非生殖个体分化两类,包括群体成员对环境的感知、相关信息的传递、个体对外部信息的生理响应、激素调控途径等环节。个体类型和生理状态信息主要以表皮碳氢化合物和挥发性信息素为媒介。品级主要受脑激素(BH)、蜕皮激素(MH)和保幼激素(JH)调节,其中JH水平对品级决定有重要影响。MH和JH的上游信号包括脑激素、胰岛素、生物胺、生长因子等信号,下游信号包括基因组、凋亡决定、储存蛋白和表观遗传等信号。在未来研究中,对营养因子信号、蜕皮激素的作用和表观遗传学途径应给予更多关注。  相似文献   

3.
The brain and the thoracic ganglion of crustacean can synthesize and secrete gonad-stimulating hormone (GSH) which stimulates the maturation of gonad. In the previous experiments, sex steroid hormones (estradiol, testosterone, progesterone, etc.) have been detected from crustacean. However, the feedback regulation of sex steroid hormones on the brain and thoracic ganglion of crustacean has not been reported so far. In the present experiment, monoclonal antibodies were applied to investigate the immunorecognition of estrogen receptor (ER) and androgen receptor (AR) in the brain and thoracic ganglion mass of Scylla paramamosain. The results showed that the distribution of the immunopositive substances of ER and AR was extremely similar. They distributed in the protocerebrum, deutocerebrum and tritocerebrum of the brain, and mainly in protocerebrum. In the thoracic ganglion mass, immunopositive substances distributed in the subesophageal ganglion, thoracic ganglion and abdomen ganglion, and mostly in subesophageal ganglion. Immunopositive substances of ER and AR mostly existed in the cytoplasm of neurons. The present study will provide morphological evidence for the origin and evolution of ER and AR. In addition, the immunoreactivities of ER and AR suggested that the estrogen and androgen may be involved in the feedback regulation of crustacean neuroendocrine.  相似文献   

4.
The brain and the thoracic ganglion of a crustacean can synthesize and secrete gonad-stimulating hormone (GSH) which stimulates the maturation of gonad. In the previous experiments, sex steroid hormones (estradiol, testosterone, progesterone, etc.) have been detected from the crustacean. However, the feedback regulation of sex steroid hormones on the brain and the thoracic ganglion of the crustacean has not been reported so far. In the present experiment, monoclonal antibodies were applied to investigate the immunorecognition of estrogen receptor (ER) and androgen receptor (AR) in the brain and the thoracic ganglion mass of Scylla paramamosain. The results showed that the distribution of the immunopositive substances of ER and AR was extremely similar. They distributed in the protocerebrum, deutocerebrum and tritocerebrum of the brain, and mainly in protocerebrum. In the thoracic ganglion mass, immunopositive substances distributed in the subesophageal ganglion, thoracic ganglion and abdominal ganglion, and mostly in subesophageal ganglion. Immunopositive substances of ER and AR mostly existed in the cytoplasm of neurons. The present study will provide morphological evidence for the origin and the evolution of ER and AR. In addition, the immunoreactivities of ER and AR suggested that the estrogen and androgen may be involved in the feedback regulation of crustacean neuroendocrine.  相似文献   

5.
The brain and the thoracic ganglion of crustacean can synthesize and secrete gonad-stimulating hormone (GSH) which stimulates the maturation of gonad. In the previous experiments, sex steroid hormones (estradiol, testosterone, progesterone, etc.) have been detected from crustacean. However, the feedback regulation of sex steroid hormones on the brain and thoracic ganglion of crustacean has not been reported so far. In the present experiment, monoclonal antibodies were applied to investigate the immunorecognition of estrogen receptor (ER) and androgen receptor (AR) in the brain and thoracic ganglion mass of Scylla paramamosain. The results showed that the distribution of the immunopositive substances of ER and AR was extremely similar. They distributed in the protocerebrum, deutocerebrum and tritocerebrum of the brain, and mainly in protocerebrum. In the thoracic ganglion mass, immunopositive substances distributed in the subesophageal ganglion, thoracic ganglion and abdomen ganglion, and mostly in subesophageal ganglion. Immunopositive substances of ER and AR mostly existed in the cytoplasm of neurons. The present study will provide morphological evidence for the origin and evolution of ER and AR. In addition, the immunoreactivities of ER and AR suggested that the estrogen and androgen may be involved in the feedback regulation of crustacean neuroendocrine.  相似文献   

6.
7.
8.
卵泡刺激素(FSH)是一种垂体前叶合成和分泌的糖蛋白激素,是卵巢发育的重要激素,可与卵巢颗粒细胞膜上的特异性受体结合从而促进细胞的增殖分化,激活细胞内芳香化酶生成雌激素和孕激素。FSH在卵巢颗粒细胞中主要依靠cAMP—PKA信号通路促进细胞增殖,同时也发生多种信号通路,ERK1/2、ERK5、p38MAPK、P13K/Akt、VEGF均参与FSH促进卵巢颗粒细胞的增殖分化;它们之间相互作用促进卵巢颗粒细胞的增殖。  相似文献   

9.
10.
本文研究了甲状腺激素减少时,小鼠的大脑、小脑、海马、嗅脑等脑组织中一氧化氮合酶(NOS)含量的变化.采用丙硫氧嘧啶(PTU)持续灌注20日龄左右雌性昆明小鼠造成甲减模型.采用NOS的生化测定法检测甲减小鼠的大脑、小脑、嗅脑、海马等中的NOS含量;检测指标包括组织中总一氧化氮合酶(TNOS)活性,以及诱导型一氧化氮合酶(iNOS)及结构型一氧化氮合酶(cNOS)两种分型酶的活性.生化测定法显示,甲状腺功能低下小鼠NOS含量与对照组比较在大脑、小脑和嗅脑中均出现了下降,cNOS在大脑、小脑、海马、嗅脑部位也均出现了下调.而iNOS含量在甲状腺功能低下小鼠的大脑、小脑、海马、嗅脑中却出现了上调.由此可得出,甲状腺激素的分泌异常会造成NOS含量的异常,NO信号系统可能参与甲状腺激素缺乏所致的脑损害过程.  相似文献   

11.
Regulation of activin A in cell proliferation as well as hCG and progesterone secretion was investigated using primary cultured cytotrophoblast cells and normal placenta origin cytotrophoblast cell line-NPC cells in serum-free system. It was shown that activin A promoted hCG and progesterone secretion in primary cultured cytotrophoblast cells as well as progesterone secretion in NPC cells, while it had no effect on cell proliferation and hCG secretion in NPC cells. Important evidence is provided for the autocrine regulatory mechanism of activin A on hormone secretion in placental trophoblast cells at early pregnancy.  相似文献   

12.
13.
14.
H Nawa  T Hirose  H Takashima  S Inayama  S Nakanishi 《Nature》1983,306(5938):32-36
The primary structures of two types of bovine brain substance P precursors have been determined. One precursor contains a sequence homologous to that of the amphibian peptide kassinin. This new tachykinin sequence is bounded by paired basic amino acids Lys-Arg, which suggests that, like substance P, it can be liberated from the precursor and may serve as an endogenous hormone or neuromediator in mammalian organisms.  相似文献   

15.
RANK ligand (RANKL), a TNF-related molecule, is essential for osteoclast formation, function and survival through interaction with its receptor RANK. Mammary glands of RANK- and RANKL-deficient mice develop normally during sexual maturation, but fail to form lobuloalveolar structures during pregnancy because of defective proliferation and increased apoptosis of mammary epithelium. It has been shown that RANKL is responsible for the major proliferative response of mouse mammary epithelium to progesterone during mammary lactational morphogenesis, and in mouse models, manipulated to induce activation of the RANK/RANKL pathway in the absence of strict hormonal control, inappropriate mammary proliferation is observed. However, there is no evidence so far of a functional contribution of RANKL to tumorigenesis. Here we show that RANK and RANKL are expressed within normal, pre-malignant and neoplastic mammary epithelium, and using complementary gain-of-function (mouse mammary tumour virus (MMTV)-RANK transgenic mice) and loss-of function (pharmacological inhibition of RANKL) approaches, define a direct contribution of this pathway in mammary tumorigenesis. Accelerated pre-neoplasias and increased mammary tumour formation were observed in MMTV-RANK transgenic mice after multiparity or treatment with carcinogen and hormone (progesterone). Reciprocally, selective pharmacological inhibition of RANKL attenuated mammary tumour development not only in hormone- and carcinogen-treated MMTV-RANK and wild-type mice, but also in the MMTV-neu transgenic spontaneous tumour model. The reduction in tumorigenesis upon RANKL inhibition was preceded by a reduction in pre-neoplasias as well as rapid and sustained reductions in hormone- and carcinogen-induced mammary epithelial proliferation and cyclin D1 levels. Collectively, our results indicate that RANKL inhibition is acting directly on hormone-induced mammary epithelium at early stages in tumorigenesis, and the permissive contribution of progesterone to increased mammary cancer incidence is due to RANKL-dependent proliferative changes in the mammary epithelium. The current study highlights a potential role for RANKL inhibition in the management of proliferative breast disease.  相似文献   

16.
17.
为探讨奶牛血液生殖激素浓度随不同胎次的变化规律及相关性和回归关系,用ELISA法测定了48头奶牛促卵泡激素(FSH)、促黄体激素(LH)、绒毛膜促性腺激素(β-HCG)、睾酮(T)、孕酮(P)和雌二醇(E2)的浓度,分析了激素浓度胎次间的相关关系和回归方程.结果表明,HCG浓度以第0、1胎为最高和最低(p<0.05);P、LH和E2浓度均以第三胎最高,各胎次P浓度差异极显著(p<0.01),第3胎与第1、2胎E2浓度差异显著(p<0.05).各胎次间FSH和T浓度差异不显著(p>0.05);胎次与六种激素以及各激素间的相关性均很小,胎次与孕酮(P)和促卵泡激素(FSH)呈负相关,FSH与LH、T和E2为负相关,LH与E2间的相关性具有显著性(p<0.05);六种激素与胎次回归方程的截距A和回归系数均不相同.  相似文献   

18.
为了解生长激素受体(GHR)基因多态性在江苏汉族人群中的分布,通过多重PCR及PCR-RFLP的方法对269例江苏地区正常汉族人进行GHR基因3个位点的多态性分析,并与文献中报道的其它种族和地区的人群进行比较分析.结果显示江苏地区汉族正常人群中GHR基因型以fl/fl、I/L、P/P发生频率最高,这种分布在男女之间没有差异,与其它地区汉族人比较没有明显差异,与日本人差异也不明显,而与法国、俄罗斯人差异明显.研究表明,GHR基因3个位点多态性在不同种族之间分布存在着明显的差异,这种差异有可能是导致不同种族间人体测量学差异及对一些疾病的易感性及对药物的反应性不同的因素之一.  相似文献   

19.
High brain densities of the immunophilin FKBP colocalized with calcineurin.   总被引:29,自引:0,他引:29  
The immunophilins cyclophilin and FK506 binding protein (FKBP) are small, predominantly soluble proteins that bind the immunosuppressant drugs cyclosporin A and FK506, respectively, with high affinity, and which seem to mediate their pharmacological actions. The Ca(2+)-dependent protein phosphatase, calcineurin, binds the cyclophilin-cyclosporin A and FKBP-FK506 complexes, indicating that calcineurin might mediate the actions of these drugs. A physiological role for the immunophilins in the nervous system is implied by a close homology between the structure of NINA A, a protein in the neural retina of Drosophila, and cyclophilin, as well as by the high density of FKBP messenger RNA in brain tissue. Here we report that the levels of FKBP and mRNA in rat brain are extraordinarily high and that their regional localization is virtually identical to that of calcineurin, indicating that there may be a physiological link between calcineurin and the immunophilins. We also show that at low concentrations FK506 and cyclosporin A enhance the phosphorylation of endogenous protein substrates in brain tissue and in intact PC12 cells, indicating that these drugs may inhibit phosphatase activity by interacting with the immunophilin-calcineurin complexes.  相似文献   

20.
为了找出能够准确反映雌性哺乳动物体内血浆孕酮(P4)波动的检测方法,实验以多浪绵羊和塔里木马鹿为实验动物,分别对其发情周期各阶段的血液样本外周血雌二醇(E2),P4与促黄体生成素(LH)含量进行了放射免疫分析(RIA)测定。发现,应用E2 P4比值比传统的方法更能准确反映雌性哺乳动物体内血浆孕酮含量的波动情况。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号