Receptor最新文献_第4页

Bioactive Arg-Gly-Asp conformations in anti-integrin GPIIb-IIIa antibodies. 抗整合素GPIIb-IIIa抗体的生物活性Arg-Gly-Asp构象。

Receptor Pub Date : 1994-01-01

K V Prammer, J Boyer, K Ugen, S J Shattil, T Kieber-Emmons

{"title":"Bioactive Arg-Gly-Asp conformations in anti-integrin GPIIb-IIIa antibodies.","authors":"K V Prammer, J Boyer, K Ugen, S J Shattil, T Kieber-Emmons","doi":"","DOIUrl":"","url":null,"abstract":"Antibodies can mimic the biological function of physiological ligands, yet few examples indicate the structural similarity between antibodies and the ligands that they mimic. Originally, the competition of antibodies for ligand binding sites was conjectured to be through similar three-dimensional conformations, which represent the \"internal image\" of the given ligand. Here we show that residues in a complementary determining region (CDR) can adopt the same bioactive structures observed in ligands. Structure-function studies of three anti-GPIIb-IIIa murine monoclonal antibodies, PAC-1, LJ-CP3, and OP-G2, indicate that the RYD sequence in their H-CDR3 domain occupies the same conformational space as RGD in conformationally constrained, bioactive, GPIIb-IIIa cell-surface adhesion ligands. The relative location of the guanidinium and carboxylate groups in the RXD regions is identified as an important recognition feature, and the conformational space occupied by this region in the antibodies is only slightly larger than that in the most bioactive peptides. Additionally, we show that antibodies can unveil other potential bioactive sequences, which may impart specificity. Thus antibodies are an exquisite probe for identifying motifs of short adhesion stretches, thereby revealing amino acid sequences and restricted geometries that might be used as lead compounds in drug design.","PeriodicalId":21112,"journal":{"name":"Receptor","volume":"4 2","pages":"93-108"},"PeriodicalIF":0.0,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18532441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interactions among prostaglandin receptors. 前列腺素受体之间的相互作用。

Receptor Pub Date : 1994-01-01

B Ashby

引用次数: 0

Regulation of prostaglandin synthesis by glucocorticoids. 糖皮质激素对前列腺素合成的调节。

Receptor Pub Date : 1994-01-01

J L Masferrer, K Seibert

引用次数: 0

Alpha 1-adrenergic stimulation of phospholipase C activity in purified cardiac sarcolemmal membranes. α 1-肾上腺素能刺激纯化心肌肌层磷脂酶C活性。

Receptor Pub Date : 1994-01-01

J T Meij, V Dhalla, V Panagia

{"title":"Alpha 1-adrenergic stimulation of phospholipase C activity in purified cardiac sarcolemmal membranes.","authors":"J T Meij, V Dhalla, V Panagia","doi":"","DOIUrl":"","url":null,"abstract":"Cardiac sarcolemmal (SL) phospholipase C (PLC) is a key enzyme in the signal transduction of several cardiac receptors. Thus, the earlier described Ca(2+)-stimulated SL PLC activity may represent variously coupled enzymes. The present study was undertaken to delineate the alpha 1-adrenoceptor/G protein-stimulated PLC activity in purified cardiac SL vesicles. Although certain detergents and membrane pore formers enhanced SL PLC activity, measured as formation of 3H-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] from 3H-phosphatidylinositol 4,5-bisphosphate, alpha 1-adrenoceptor stimulated activity was not observed. When SL vesicles were preincubated (0-4 degrees C) with substrate in detergent-free buffer, subsequent incubation (37 degrees C; in mM: 100 NaCl, 2 EGTA, 1.8 CaCl2, 10 LiCl) resulted in a time-dependent production of 3H-Ins(1,4,5)P3, that was increased in the presence of 100 microM GTP gamma S. GTP gamma S stimulation of SL PLC activity required the presence of Mg2+ and Ca2+, but was lost at (sub)millimolar concentrations of these bivalent cations. Mg2+ (0.01-10 mM) promoted a 2,3-diphosphoglycerate-insensitive phosphatase activity. GTP gamma S enhanced the sensitivity of SL PLC to Ca2+, but did not increase the maximum Ca2+ (0.1-1 mM) stimulated SL PLC activity. At 5 microM Ca2+, GTP gamma S induced a concentration-dependent rise in inositol phosphates production, which was further elevated by the alpha 1-agonist, phenylephrine (PhE). The PhE-effect was inhibited by the alpha 1-antagonist prazosin, but not by the beta-antagonist atenolol. These results show that the components necessary for the alpha 1-adrenoceptor transmembrane signal are associated with the SL membrane and can be functionally coupled.","PeriodicalId":21112,"journal":{"name":"Receptor","volume":"4 2","pages":"109-19"},"PeriodicalIF":0.0,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18946887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evidence for chemical differentiation of delta opioid receptor subtypes by the sulfhydryl reagent N-ethylmaleimide. 巯基试剂n -乙基马来酰亚胺对阿片受体亚型化学分化的证据。

Receptor Pub Date : 1994-01-01

L Tam, M F Rafferty

{"title":"Evidence for chemical differentiation of delta opioid receptor subtypes by the sulfhydryl reagent N-ethylmaleimide.","authors":"L Tam, M F Rafferty","doi":"","DOIUrl":"","url":null,"abstract":"In this study, the delta receptor-selective nonequilibrium affinity ligands, 5'-NTII and DALCE, and the nonspecific sulfhydryl reagent NEM were evaluated over a range of concentrations and treatment conditions for their ability to selectively alter the binding properties of delta 1- or delta 2-preferring opioid radioligands in brain homogenate. Treatment of tissue preparations with DALCE (0-10,000 nM) or NTII (0-10,000 nM) resulted in an equivalent concentration-dependent loss of binding capacity for the delta 1 agonist 3H-DPDPE and the mu/delta 2 agonist 3H-DSLET. In contrast, treatment of tissue with NEM (0-8000 microM) resulted in greater loss of 3H-DPDPE binding. Scatchard analysis of the binding of 3H-DPDPE, 3H-DSLET, and 3H-NTI in 3 mM NEM-treated rat brain P2 preparation revealed an equivalent decrease in affinity for the agonist ligands, but a significantly greater decrease in Bmax for 3H-DPDPE compared with control tissue values. Comparison of the K(i) values for a series of delta-selective compounds against 3H-DSLET binding in control vs 3 mM NEM treated P2 fraction showed differential effects of NEM on affinity within the series that were consistent with a selective depletion of delta 1 sites. Overall, these results indicate that NEM treatment selectively reduced delta 1 receptor binding, resulting in a preparation that is enriched in delta 2 sites.","PeriodicalId":21112,"journal":{"name":"Receptor","volume":"4 2","pages":"81-91"},"PeriodicalIF":0.0,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18946890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

DNA sequence requirements for Ah receptor/Arnt recognition determined by in vitro transcription. 通过体外转录确定Ah受体/Arnt识别所需的DNA序列。

Receptor Pub Date : 1994-01-01

K E McLane, J P Whitlock

引用次数: 0

Functional expression of a mouse growth hormone receptor cDNA in transfected mouse L cells. 小鼠生长激素受体cDNA在转染小鼠L细胞中的功能表达。

Receptor Pub Date : 1994-01-01

Y Zhou, B Xu, X Wang, W Y Chen, J J Kopchick

引用次数: 0

Localization and diffusion of glucagon receptor in rat hepatocytes. 胰高血糖素受体在大鼠肝细胞中的定位和扩散。

Receptor Pub Date : 1994-01-01

S S Gupte

{"title":"Localization and diffusion of glucagon receptor in rat hepatocytes.","authors":"S S Gupte","doi":"","DOIUrl":"","url":null,"abstract":"The lateral diffusion rate of glucagon receptor in rat hepatocyte plasma membrane in the absence and presence of glucagon was measured to be approximately 7.0 x 10(-10) cm2/s. The percentage of glucagon receptor molecules remaining on the cell surface after the activation of signal transduction process by 100 nM glucagon was approximately 74% of its original number. Although the number of glucagon receptors on the plasma membrane capable of interacting with its signal transduction partners decreases on addition of glucagon, the lateral diffusion rate and the percentage of mobile receptors remain essentially unchanged. A hypothesis has been developed that for signal transduction to occur, the random diffusion-dependent collision of one, two, or all three components is an essential part, and it may be the rate-limiting step. An approximate calculation has been made of random diffusion-dependent theoretical and experimental collision frequencies using experimentally measured concentrations and reasonable value for diffusion rate of G protein to investigate the role of diffusion in signal transduction. These calculations indicate that the diffusion of individual components is important and may be the rate-limiting step in the signal transduction process. The diffusion rate and percent mobile fraction of glucagon receptor data presented in this article are the first step toward elucidating the validity of the diffusion-dependent signal transduction hypothesis.","PeriodicalId":21112,"journal":{"name":"Receptor","volume":"4 3","pages":"175-90"},"PeriodicalIF":0.0,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18812327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The concentration of LH-RH receptors in the nuclei of pancreatic cancer cells. Effect of (D-Trp6)LH-RH on tumor-bearing Syrian golden hamsters. 胰腺癌细胞核中rh - rh受体的浓度。(D-Trp6)LH-RH对荷瘤叙利亚金仓鼠的影响。

Receptor Pub Date : 1994-01-01

B Szende, A Csikós, K Szepeshazi, J D Neill, J J Mulchahey, G Halmos, K Lapis, A V Schally

引用次数: 0

Neutrophil-platelet interactions in inflammation. 炎症中的中性粒细胞-血小板相互作用。

Receptor Pub Date : 1994-01-01

M A Selak

引用次数: 0