Receptors defined

The actions of histamine are mediated through at least three distinct receptors defined pharmacologically by the actions of the respective agonists and antagonists. Reviews have been pubHshed (16,17). 

The presence of a specific receptor defines the target cells for a given hormone. 

The spectral map shows three distinct poles of specificity. These are respectively the p-receptor (DHM), the 6-receptor (DADLE) and the K-receptor (EKC). The naloxone receptor (NAL) appears to be strongly correlated with the p-receptor (DHM) and, hence, provides little additional information. In spectral map analysis, correlation between variables, as well as similarity between compounds, is evidenced by the proximity of their corresponding symbols. The lines drawn through the three poles of the map represent bipolar axes of contrast. A contrast is defined in this context as a log ratio or, equivalently, as a difference of logarithms. For example, the horizontal axis through the p- and 8-receptors defines the p/6 contrast. Compounds that project on the right side of this axis bind more specifically to the p-receptor, while those that project on the left side possess more... 

Marchese AM et al. Discovery of three novel orphan G-protein-coupled receptors. Genomics 1999 56 12-21. Bertilsson G et al. Identification of a human nuclear receptor defines a new signaling pathway for CYP3A induction. Proc Natl Acad Sci USA 1998 95 12208-12213. 

Bertilsson, G., Heidrich, J., Svensson, K., Asman, M., Jendeberg, L., Sydow-Backman, M., Ohlsson, R., Postlind, H., Blomquist, P. and Berkenstam, A. (1998) Identification of a human nuclear receptor defines a new signaling... 

The normal internalization of the wild-type receptor, defined as a loss of cell surface receptors (measured by decreased maximal binding or B ), was unaffected for the desensitization-deficient Thr mutant (see Fig. 6.4C,D) but may have been affected when distal carboxyl terminal residues were mutated (see Fig. 6.3). Therefore some, although not all, GPCRs show radical dissociation between desensitization and internalization. This is found not only in the dopamine Dj receptor (122) but also in the N-formyl peptide (134), the CBl cannabinoid (17), and the M2 muscarinic (155) receptors. 

The conservation equation for receptors defines the total number of receptors as the sum of bound and free receptors (Equation (6.3)). Although the receptor population is in fact made up of subpopulations of receptors in high- and low-affinity states, this is most relevant for modeling agonist interactions. Because most tracers are radiolabeled antagonists, this simplified model is sufficient for most tracer studies. The conservation and mass action equations (Equations (6.3) and (6.4)) can be rearranged to calculate the number of bound receptors ... 

Analysis of the soluble G-bead assembly provides a complementary classification of full and partial agonists, based on their distinct abilities to assemble ternary complexes (LRG). It appears that the behavior of receptors and entire ligand families can be described by the simple ternary complex model alone (Fig. 2A). The analysis provides estimates for the ligand-dependent equilibrium constants that govern the simple ternary complex model. Unique, potentially intermediate, conformational states of the receptor defined by interactions with a particular ligand are characterized by individual binding constants. While these data do not directly show these different conformational states, the bead system appears to act as a... 

Julius D, Huang KN, Livelli TJ, Axel R, Jessell TM. The 5HT2 receptor defines a family of structurally distinct but functionally conserved serotonin receptors. Proc Natl Acad Sci USA 1990 87 928-932. 

Matthes H, Boschert U, Amlaiky N, et al. Mouse 5-hydroxytiyptamine5A and 5-hydroxytryptamine5B receptors define a new family of serotonin receptors cloning, functional expression, and chromosomal localization. Mol Pharmacol 1993 43 313-319. 

The 5-hydroxytryptamine3 (5-HT3) receptor contains an integral, agonistgated ion channel and in this way differs from all other known serotonin receptors whose actions are mediated via G proteins (1). 5-HT3 receptors were one of the original two classes of serotonin-activated receptors defined by Gaddum and Picarrelli (2). Seven distinct classes have now been defined, but, to date, the 5-HT3 receptor is the only vertebrate 5-HT-gated ion channel known indeed, it is more closely related to the nicotinic acetylcholine (nACh) receptor than to any of these other classes of 5-HT receptor. 

Seetharam B. Receptor-mediated endocytosis of cobalamin (vitamin B12). Annu. Rev. Nutr. 1999 19 173-195. Boonyarattanakalin S, Martin SE, Sun Q, Peterson BR. A Synthetic Mimic of Human Fc Receptors Defined Chemical Modification of Cell Surfaces Enables Efficient Endocytic Uptake of Human Immunoglobulin-G. J. Am. Chem. Soc. 2006 128 11463-11470. 

Tandon NN, Harmon JT, Rodbard D, Jamieson GA Thrombin receptors define responsiveness of cholesterol-modified platelets. J Biol Chem 258 11840,1983... 

Tandon, N., Harmon, J. T., Rodbard, D. and Jamieson, G. A. Thrombin receptors define responsiveness... 

Nicotine and neonicotinoids are agonists, both of which act at the nicotinic acetylcholine receptor -Na" /K+ ionophore. The structural differences between the insect and mammalian receptors define the selectivity of neonicotinoid toxicity to insects and nicotine toxicity to vertebrates. The proposed concept of the neonicotinoid electronegative pharmacophore... 

Faucette SR, Zhang TC, Moore R, Sueyoshi T, Omiecinski C, LeCluyse EL, et al. Relative activation of human pregnane X receptor versus constitutive androstane receptor defines distinct classes of CYP2B6 and CYP3A4 inducers. J Pharmacol Exp Ther 2007 320 72-80. 

Dussault I, Lin M, Hollister K, Wang EH, Synold TW, Forman BM. A structural model of the constitutive androstane receptor defines novel interactions that mediate hgand-independent activity. J Biol Chem 2001 276 33309-12. 

Five pharmacophore point types are used to generate PDT fingerprints hydrogen-bond acceptor atom, hydrogen-bond donor atom, acceptor site, donor site, and hydrophobic center. While donor and acceptor atoms are part of the molecule, site points refer to interaction points located on a virtual receptor defined by geometrical criteria [Martin, Bures et al., 1993]. Interfeature distances from 2.5 to 15.0 A are divided into 27 distance bins of equal width (i.e.,... 

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