Receptors isolation

Kieffer BL, Befort K, Gaveriaux-Ruff C, Hirth CG. The 6-opioid receptor isolation of a cDNA by expression cloning and pharmacological characterization. Proc Natl Acad Sci USA 1992 89 12048-12052. 

Estradiol. The first neuroactive steroid receptor type to be recognized was that for estradiol [3]. In vivo uptake of [3H] estradiol, and binding to cell nuclei isolated from hypothalamus, pituitary and other brain regions, revealed steroid specificity closely resembling that of the uterus, where steroid receptors were first discovered [3]. Cytosolic estrogen receptors isolated from pituitary and brain tissue closely resemble those found in uterus and mammary tissue. A hallmark of the estrogen receptor is its existence... 

Salminen O, Drapeau J, McIntosh JM, CoUins AC, Marks MJ, Grady SR (2007) Pharmacology of a-conotoxin Mil-sensitive subtypes of nicotinic acetylcholine receptors isolated by breeding of null mutant mice. Mol Pharmacol 71 1563-1571... 

Effects on cell function determine whether the drug is an agonist, partial agonist, or antagonist at the relevant receptors. Isolated tissues, especially vascular smooth muscle, would be used to characterize the pharmacologic activity and selectivity of the new compound in comparison with reference compounds. Comparison with other drugs would also be undertaken in other in vitro preparations such as gastrointestinal and bronchial smooth muscle. At each step in this process, the compound would have to meet specific performance and selectivity criteria to be carried further. 

Kieffer, B.L., Befort, K., Gaveriaux-Ruff, C., Hirth, C.G. The 8 opioid receptor, isolation ofcDNA clone by expression cloning and pharmacological characterization, Proc. Natl. Acad. Sci. USA 1992, 89, 12048-12052. 

Use of microorganisms and plant and animal tissues as a biological component of biosensor are also described in the literature (9, 10). The principle is based on the use of the natural bio-reactive systems. They have several advantages over the isolated enzymes and receptors. Isolation of enzymes and receptors are often required to increase the response time. Enzymes and receptors retained in the cells are more stable and have longer lifetimes. Cell-based biosensors are also economical as no purification step is required. 

The blockade of A3AR with the selective antagonist, MRS 1334, improves the stability of GABAAergic neurotransmission, as assessed in a patch clamp study on GABAa receptor isolated from neurosurgically resected epileptic human nervous tissues and microtransplanted into Xenopus oocytes, and on human epileptic slices obtained from neurosurgical resection (Roseti et al. 2008). 

The first step in the biochemical analysis of the receptor, isolation from the cell membrane, was difficult the membrane-associated protein is present in only small amounts and is insoluble in aqueous solution. Sensitivity and selectivity would be improved by radiolabeling under conditions that maintain cell viability so that only proteins associated with the surface and not those within the cell become labeled. A procedure that met these conditions was iodination catalyzed by lactoperoxidase in the presence of hydrogen peroxide (Marchalonis, 1969 Phillips and Morrison, 1970 Marchalonis et al., 1971). It was also necessary to find conditions for solubilizing membrane proteins that would not interfere with subsequent specific immunoprecipitation. 

Hahn ME, Westler WM, Sicinski RR, De-Luca HF (2002) A ligand for the aryl hydrocarbon receptor isolated from lung. 

Nicotinic acetylcholine receptor Receptor, isolated from electro-phorus electricus, was incorporated into a polymeric film formed in situ on an electronic transductor containing two terminal 1.5 cm x 1.5 cm interdigitated gold electrode. The response of the biosensor reached equilibrium within 5 s for ACh and remained stable up to 20 min. Detection limits 25 ng in a 50 pL sample (i.e., 0.5 pg/mL). [93]... 

Although in total four sites of phosphorylation have been defined, phosphopep-tide mapping of the EGF receptor isolated from cultured cells suggests that several other sites are modified, including serine residues. The enzymes responsible for this and the effect on the receptor are not known. 

Chorionic growth-hormone prolactin. 845 Christmas factor, recombinant. 185 Chromatography affinity, in receptor isolation. 28 in combinatorial clicmisiry. 51 high-pcfformancc liquid. 51. 833 ion exchange. 8.34 paper. 834... 

Z3.3 In Vitro AsKiys for Efficacy. Until the cloning of the opioid receptors isolated tissue preparations, particularly smooth muscle preparations, were used extensively to characterize opioids (see Refs. 131,132 for reviews). The electrically stimulated GPI myenteric plexus-longitudinal muscle and the MVD... 

Tritiated affinity labels have been useful in receptor isolation and for determination of the molecular weights of solubilized receptors (see Refs. 86, 99 for reviews). These compounds can be used to irreversibly block one or more receptor type in tissues containing multiple receptor types, so that the remaining receptors c be studied in isolation. The covalent binding cf affinity labels can be used to study receptor-ligand interactions. Thus Liu-Chen and coworkers have characterized the binding of the affinity labels j3-funaltrexamine (j8-FNA) and SUPER-FIT to ju. and S receptors, respectively, by use of a combination of molecular biology approaches and protein isolation (see below). 

Song, J., M. Clagett-Dame, R.E. Peterson, M.E. Hahn, W.M. Westler, R.R. Sicinski and H.F. DeLuca. A ligand for the aryl hydrocarbon receptor isolated from lung. Proc. Natl Acad. Sci. USA 99 14694-14699, 2002. 

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